How to Use Semantic Keywords for SEO

What makes your business successful? More revenue and more clients. But to get customers to call you or visit your store in today’s online world, you know you need to appear at the top of Google Search. You also probably understand that keywords are critical, but do you know which keywords to use and how to leverage semantic keywords to ensure more people find your content and your company online?

Keep reading to discover everything you need to know to effectively use semantically-related keywords for marketing your website and your organization smarter. In this article, you’ll learn:

Plus, we’ll illustrate those ideas with relevant examples to help clarify semantic keywords and how to add them to your content marketing arsenal.

1. What are Semantic Keywords

Before you can understand semantic keywords, you need to learn a little bit about what semantics is.

What is semantics?

According to Oxford University’s Lexico, semantics is the branch of linguistics and logic that looks at meaning. There are many branches of semantics, including:

  1. Formal semantics – the study of the logical aspects of meaning
  2. Conceptual semantics – the study of the cognitive structure of meaning
  3. Lexical semantics – the study of word meanings and word relations

In terms of semantic keywords, your main concern is going to be lexical semantics. In other words, how the meanings of your keywords as well as words and phrases that are related to your primary keywords.

Examples of semantics

It’s easy to get bogged down in the complexities of semantics, so let’s take a look at three examples:

  • The adjective “square” might refer to a box, a cube, a shape, or be old fashioned slang for a person who is average and adheres to the rules and the status quo.
  • The noun “plant” could be a bush, flower, weed, tree, or a factory.
  • The term “crash” might refer to a car accident, a sudden drop in energy levels, a loud noise as the result of something falling, or a rapid decline in the stock market.

Put simply, the meaning of a word often depends on the context and meaning of other words in the same sentence, paragraph, or overall content. When a word or phrase can have multiple meanings, we immediately understand which one it is, by its relationship to other words, including semantically related terms and phrases.

Semantically related words aren’t synonyms per se, but words and phrases that convey the context and meaning of a passage, topic, or theme.
But what does this mean when it comes to search engine optimization and keyword research? Keep reading to find out.

What are Latent Semantic Indexing keywords?

Now that you’re delving into the meaning of keywords and linguistics, you might be worried about over complicating or misunderstanding what you have to research or analyze and optimize your content for. You do not have to become a linguist or philosopher to understand how to apply semantics to your SEO and content creation efforts.

But before we get into that, what are LSI keywords?

Latent Semantic Indexing is a technology from mathematics. It’s now used by Google and others to analyze text and determine the meaning of the text.

Latent Semantic Indexing (LSI) in the SEO world are in reference to keywords and phrases that are semantically related to your primary keywords. Thus, the terms LSI keywords and semantic keywords are describing the same types of keywords and no matter which term you refer, they help boost your content because of their high degree of relevance to your content’s primary keyword.

Examples of semantic keywords

When you’re looking to optimize your content for LSI, it’s essential to understand that they are not the same thing as synonyms. While using synonyms is good for on-page SEO and to avoid accidental keyword stuffing, that tactic is not the same as using semantics to improve your online content. So, what are some examples of semantics?

Example 1: A Bakery

If your bakery website has a blog post with the primary keyword, “how to bake a cake,” your keywords might include words like:

  • Flour
  • Baking pan
  • Eggs
  • Frosting
  • Marzipan
  • Chocolate
  • Oven temperature
  • Baking
  • Desserts

None of the above terms are synonyms. Still, they all help your reader and search engines understand the context and relevance of your article to a search query.

Example 2: An HVAC Contractor

Maybe you’re not a baker but own an HVAC contracting and repair business. You might instead have a primary keyword like “air conditioner repair.” In that case, your keyword list might include:

  • Cooling
  • Summer
  • Hot air
  • Bad smell
  • Burning
  • 24-hour service
  • Maintenance
  • Professional help
  • Emergency help

You’ll notice that some of the above phrases could be used in multiple contexts, including content that’s not about heating and cooling at all. However, when used in content that includes your primary keyword, it’s evident to your customers and Google that the web page or article is about “air conditioner repair” and that an LSI word like “hot air” refers to an AC unit and not something like a hot air balloon.

2. Why LSI Keywords are Important

Now that you know what semantics are in relation to keywords and what they are not, what is their significance in terms of helping your website and your content appearing on page one of Google search results? And, more importantly, drive customers to your business? Aren’t primary keywords enough?

Early days of SEO and keywords

In the early days of SEO, you used to be able to get away with all kinds of things to dominate search and get found online. It wasn’t uncommon to see web pages with hidden content that was nothing but keywords, or for content that made almost no sense but was stuffed with a primary keyword. Later, that kind of strategy became frowned on because it didn’t help searchers, but keywords stayed.

At the time, Google, Bing, and other search engines weren’t good at identifying search intent or the context of your content, and using primary keywords several times within a page of content was crucial.

Flash forward to today and numerous Google algorithm updates plus advances in machine learning, and AI, resulting in more advanced ways for the search giant to rank your website and your content. Most recently, Google’s October 2019 BERT update improved the search engine’s ability to understand the “context of ambiguous, complex, and confusing search queries.”

How Google determines context to rank content

According to Google, they use a variety of algorithms to look at the meaning of a piece of content and searcher intent. Besides your main keywords, the search engine looks at or incorporates the following elements:

  1. Spelling mistakes
  2. Natural language understanding
  3. Synonyms
  4. Latent Semantic Indexing

These and other methods help them determine where your content will rank for a particular searcher’s query. The more relevant your content is for a user, the more likely it will appear on the first page of their search.

How semantics reinforce your main keywords

Because Google uses LSI and similar methods to identify searcher intent and content context, when you incorporate semantically-focused keywords into your SEO strategy, your content is more likely to be found online.

LSI helps Google and your customers understand your website, your business, your services, and your products. In many ways, how they’re used to help determine what shows up in any given search query shows that the topic of a given webpage is more important than how many times your primary keywords appear in the copy.

Why LSI keywords are more important than the density of keywords in your content

We’ll go more into keyword density towards the end of the article. While you can’t ignore the importance of keyword density, you need to understand why semantics is critical for optimizing your content to appear in front of more people organically.

If you want more traffic from organic search results, you must understand the purpose of keyword selection and not just density. Furthermore, as we’ve already pointed out, Google’s search algorithms have evolved to understand the context, meaning, and searcher intent better.

And while keyword density still is a ranking factor, Google uses more signals that help them determine the relevance and context of your content to a user’s search query. Proper usage of LSI helps Google understand the topic of your pages, and that’s why they’re more important than keyword density, but do not eliminate the need for primary keyword research and use in online marketing.

So, how do you find and use the right keywords?

3. How are Semantic Keywords Used for SEO

When researching an article or web page copy, the method I most like to use is similar to the one suggested by Sujan Patel in his Search Engine Journal article, with a few variations, and not necessarily in this order.

#1 Determine your primary keyword(s)

You still must conduct topic and primary keyword research. However, you might already have a list of primary keywords your company’s website is focused on targeting. Use those to guide topic selection and semantics as well.

#2 Determine your core keywords

Next, make a list of words that are close in meaning to your primary keywords. These can be synonyms and phrases that convey the same idea as your primary keyword. Pay attention to search suggestions and related searches in Google.

#3 Make a list of thematically related keywords

The third step involves finding phrases that don’t convey the same meaning but are related to the same topic. For example, let’s go back to the person looking for air conditioning repair from the HVAC example earlier. They might have started by looking at “Best AC repair near me” or “HVAC contractor reviews” because they have an immediate problem – their AC is broken.

Therefore, a list of thematically related keywords to “Best AC repair near me” might include:

  • Busted air conditioner
  • How to find AC repair
  • Air conditioner maintenance
  • Broken air conditioner
  • AC repair
  • Home air conditioner

#4 Make a list of stem keywords that answer searcher questions

This step involves finding keywords that answer searcher questions, including questions that might arise after they began their search. You can find some of these by using the “people also ask” feature in Google search, and by analyzing the problem that the person is trying to solve, so you can anticipate the next steps they might take.

In our broken air conditioner example, you might also optimize your content for the following:

  1. Where can I purchase a new air conditioner?
  2. How to determine if you need new AC
  3. Should I repair or replace my busted air conditioner?
  4. What questions should I ask my AC repair company?
  5. Can I repair my AC myself?

#5 Outline your articles with keywords from all four lists you created

Once you’ve created your lists of LSI keywords and phrases, you’re ready to outline your articles based on the four lists you created. Furthermore, outlining your articles in advance will help guide any necessary research, and make writing the article for you or for a freelance writer much simpler.

To use the lists you’ve created, start by using a primary keyword or core LSI keyword in your title, then choose one to two keywords from your thematic and stem/question LSI keyword lists. Let’s use or combine some of our fictional HVAC contractor’s keywords to outline a blog post for their website that helps a potential customer who’s struggling with a busted AC on a hot day in Phoenix, AZ:

  • Air Conditioner Repair Guide
  • Where to find AC repair
  • Air conditioner repair vs. AC replacement
  • Can I repair my busted AC myself?

You could easily create content that covers the entire topic, and that’s optimized based on search intent and to help Google understand what your post is about so it can rank it under the relevant queries.

#6 Write for people, not for search engines

Now that we’ve talked about semantics and more advanced keyword research that prioritizes LSI keywords, the most important thing you can do to create content that shows up at the top of online searches, is to write for people.

In fact, once you find a topic to create useful content that helps your customers, you can go back and use tools during editing to incorporate more LSI keywords and eliminate any accidental overuse of keywords and other terms.

If you know and understand your target markets and your current customers, then you can create content that answers their questions, helps them solve their problems, and ensures they see your organization as the best company to turn to when they need help.

4. Tools Used for Finding Semantics

While LSI might be newer concepts to you than old fashioned keyword research, the good news is that there are tools you can use to help. The following ones are some of BizIQ’s SEO team favorites:

LSI Graph

LSI Graph will give you a limited list of core keywords for free as well as a limited list of articles on the same topic. For more advanced features and more keywords, you can choose between a basic and premium version, and there’s even an agency-level subscription.

Cost: $27/month to $444/year

LSI Keywords

LSI Keywords tool allows you to enter up to 10 keywords to generate a list of semantic keywords for free. It’s a basic but powerful tool that’s invaluable, especially when your budget is tight.

Cost: Free

Answer the Public

I love Answer the Public! It’s one of the first SEO copywriting tools I used besides Google. They changed the quirky old guy that was the feature on their homepage for a hipster-looking guy, but that’s ok. Their tool generates a list of questions and a list of prepositional phrases that allow you to create powerful lists of multi-level LSI keywords. Even the free version gives you a lot of content optimization bang.

Cost: Free to $99/month


KeyWord Finder is an affordable SEO tool that helps you do all kinds of keyword research from LSI to longtail research as well as primary keyword research. There isn’t a free version. However, you can try it out free for 10 days.

Cost: $49 to $129/month (40% off if you pay for a year at a time)

Google Autocomplete

The granddaddy of all free LSI keyword tools is the autocomplete feature in Google Search. It’s free. And it’s incredibly simple to operate. Simply follow these steps:
Open a Google search page
Type part of a query

For example, when you type “air con,” Google Autocomplete generates a list below that brings up these terms:

  • Air conditioner
  • Air conditioning
  • Air conditioning service
  • Air conditioner units
  • Air cooling
  • Air conditioned

Cost: Free

5. The Relationship Between LSI Keywords & Density

Now that you have an idea about what modern keyword research resembles, let’s go back and take a brief look at the relationship between LSI keywords and keyword density.

What is keyword density?

Keyword density is the percentage of times a particular keyword appears in a piece of content. In the past, some SEO’s recommended keyword density be as high as 10% to 13%. Still, nowadays, that would be considered keyword stuffing, and you do not want to go above a keyword density of more than 1.5% to 2%. Ideally, it’s better to write natural copy and not worry about keyword density and then edit for over usage of terms as well as focus on incorporating semantic keywords and LSI keyword density instead.

How to calculate keyword density

You can calculate your keyword density by hand. To do this, you would divide the number of times you repeat a specific keyword by the total words on a webpage or in an article and then multiply by 100 (NKR/TKN) * 100 = keyword density.

Alternatively, you can use a free tool to analyze your keyword density and your LSI keyword density as well.

Final Thoughts

As you can see, organic search and SEO have evolved far beyond basic keywords. Google now focuses more on search intent and the context of your content in relation to that intent than it does on simple keywords and phrases.

And while primary keywords are still relevant, to appear before more customers online and dominate search results, small business owners and their marketing staff members must understand the importance of LSI keywords. By focusing less on keyword density and more on optimizing for the three types of LSI keywords to support your primary keyword and topic, your content will improve and gain better rankings.

Need help with marketing your business including local and organic SEO? Contact BizIQ now to speak to an online marketing expert now.