Despite their constant evolution, search engines still rely heavily on keywords to determine a page's relevance to the search query. While keywords can be categorized according to several aspects, the most important distinction you should make is between primary and secondary keywords.
In this guide, we dive into this difference and discuss everything you should know about discovering and using secondary keywords in your content.
What you will learn
- What secondary keywords are and why they're important
- How to find secondary keywords
- Where and how to include them in your content
What are secondary keywords?
Secondary keywords are search terms semantically related to the primary/core keyword. They're typically synonyms or close variations of the primary keyword and specify it to give search engines more context as to what your content is about.
Let's say your primary keyword is "home workouts." In this case, related terms that can act as secondary keywords include the following:
- "home workout plan"
- "no equipment home workouts"
- "how to work out at home"
By adding such keywords alongside the primary keyword, you'll help Google understand precisely what your content is about — and this clarity should lead to a higher rank in search engine results pages (SERPs).
Why are secondary keywords important for SEO?
Secondary keywords support primary keywords and help your content rank higher for a broader range of relevant search queries. This means you don't need to create multiple pieces for each keyword — a single piece can be recognized as the relevant source of information for all those search terms.
The importance of secondary keywords skyrocketed after the Google Hummingbird update, which enabled search algorithms to understand the meaning behind a search term instead of simply matching individual keywords to content.
From this perspective, secondary keywords have another important task — clarifying ambiguous primary keywords.
For example, the primary keyword "apple" can refer to the fruit or the tech giant. Secondary keywords like "vitamin c" and "honeycrisp" indicate the former, while "iphone" and "cupertino" clarify that you're writing about the latter.
Including these keywords in your blog is good practice to help rank your pages.
These are commonly known as LSI (Latent Semantic Indexing) keywords, which aren't necessarily synonyms of the primary keyword but conceptually related terms.
Keep in mind that besides providing clarity, LSI keywords may not have much impact on your SEO success.
That's why the rest of this guide will focus on the more valuable forms of secondary keywords, like the ones you saw in the previous section.
How to find secondary keywords
Identifying the right secondary keywords for your content isn't too challenging. Let's go over some simple yet effective approaches.
Use Google
The first and easiest way to uncover keyword opportunities is to do the same thing as your audience — perform a quick Google search. When you do, you can find keyword ideas in three places:
- Google Autocomplete
- People also ask (PAA)
- Related searches
For example, you can start searching for "gardening tools" as your primary keyword and see what Google Autocomplete suggests.
You'll get several potential secondary keywords, as shown in this image:
You can then scroll down to the People also ask section, where you'll see additional suggestions that double as headings you can use throughout the content.
Finally, you can find the Related searches section to discover more keyword ideas.
In some cases, related searches will overlap with Google Autocomplete results, but you should be able to find a handful of fresh ideas.
A good way to know whether a search term can be used as a secondary keyword is to Google it.
If you notice many of the same search results as for the primary keyword, you can consider the query a secondary keyword.
Use a keyword tool
There are plenty of keyword research tools on the market, and many of them are free. Such tools let you enter the seed/primary keyword and find various suggestions based on Google search data.
Ideally, your chosen tool will also give you useful keyword data you can use to find the best-performing keywords (search volume, keyword difficulty, etc.).
Take Surfer for example. You can see the important keyword metrics like monthly search volume, total traffic and keyword difficulty for a keyword.
But you can also see which keywords to use within your article so you don't have to make a list of related semantic keywords.
If you haven't used keyword tools before, you can also try AnswerThePublic as a simple, beginner-friendly option.
Enter your primary keyword, choose your target country and language, and hit Search.
The platform will show you dozens of secondary keywords with their monthly search volumes and CPC (Cost per Click).
Keep in mind that not all suggestions might be usable. A good example is the first suggestion ("how to time tracking app"), which doesn't make much sense.
You can also see that there's no search data for it, which further confirms you should ignore it.
When choosing between viable keywords, keep in mind that those with an excessively high search volume are typically hard to rank for.
While there's no harm in adding them to your content (because you're trying to rank for the primary keyword anyway), prioritize keywords with fewer searches that still have a decent traffic potential.
AnswerThePublic only gives you three free searches per day when you create an account.
Your research needs will most likely evolve beyond this limitation, in which case you can try other tools like Google Keyword Planner.
Use Google Search Console
If you've already published some content, you can assess its performance using Google Search Console (GSC) to identify areas of opportunity and new keywords to target. All you need to do is follow a few simple steps:
- Open GSC and go to the Performance tab
- Click Search results
- Define your preferred date range and devices
- Check the boxes next to Total clicks, Total impressions, Average CTR, and Average position
- Scroll down to Queries
Here you'll see the search terms your pages are ranking for. You can sort them according to the above metrics (clicks, impressions, etc.) to identify the best-performing ones.
You can then optimize your content for the given keywords to improve its rank.
Use your experience
In some cases, you can find secondary keywords intuitively by relying on your industry experience. This approach is particularly common in highly technical, niche areas where you might be familiar with terms that aren't as prevalent among outsiders.
This is where you can also use industry-specific forums to see what others want to know about and find inspiration for secondary keywords.
For example, if you're in the laser cutting niche, you can use the Inventables forum and examine some hot topics. Here you'll see what others are interested in, so you can find both secondary keywords and entire topic ideas.
Keep in mind that this isn't the most reliable way to look for keywords because it involves a lot of guesswork. You can roughly assess the popularity of certain keywords, but it's always better to make data-driven decisions based on research supported by the right tools.
With that in mind, think of this method as the last resort.
How to use secondary keywords in your content
Finding the right secondary keywords for your content is only half the job done. Let's go over some of the best practices to follow while adding them to your content.
1. Include keywords naturally
While Google should recognize your efforts to rank high in search engines, your readers shouldn't.
Awkwardly placed or forced keywords damage the user experience, so pay attention to the content's flow and readability when adding secondary keywords.
One way to make this happen is to avoid focusing on your list of keywords while writing.
Doing so can be distracting and motivate you to include unnecessary or poor-quality content solely for the purpose of using a keyword.
That's why it's always best to focus on the writing and optimize your piece afterward. If you cover a topic thoroughly, many related keywords will naturally appear in the text without your conscious effort to include them.
Besides the content's body, you can (and should) include secondary keywords in subheadings. Doing so communicates a section's relevance to the main topic and primary keyword.
As an added bonus, it's an excellent way to include a tricky target keyword that may not naturally fit in a sentence.
You can also add keywords to image alt text and meta descriptions, but only if they make sense and won't feel forced.
Here's an example of a well-placed secondary keyword in an article's meta description:
As you can see, this meta description includes both the primary keyword ("best air matters") and a semantically related secondary keyword ("top air mattresses").
This brings us to another important point...
2. Prioritize your primary keywords
As mentioned, secondary keywords support your content's SEO standing, but they shouldn't guide your strategy.
Primary keywords are the ones you're trying to rank for, so you need to prioritize them and make sure they're included in the following elements:
- Page title and meta description
- URL
- Main heading (H1)
Besides the meta description, these elements shouldn't contain secondary keywords or lots of additional content.
Adding it might dillute the piece's focus and confuse search engines, preventing your content from ranking high for the primary keyword.
3. Don't stuff keywords
Keyword stuffing is one of the most dangerous SEO mistakes you can make. It goes against Google's Spam Policies and can seriously damage your content's quality and readability.
This doesn't only go the content's body but also the image alt text and captions, page titles, or meta descriptions.
Here's an example of a meta description stuffed with keywords:
As you can see, the second sentence of the meta description doesn't make much sense.
Google is good at recognizing attempts to manipulate the search algorithm, and it almost always punishes them with a low SERP rank.
This is another argument in favor of including keywords naturally in your content. Be mindful of keyword density while writing, and double-check for any excessive use of keywords.
Remember that your content is all about helping the user meet their search intent and find valuable information.
If this means you need to leave out some secondary keywords altogether, so be it — Google can still pick up on your content. As long as the primary keyword is in the right places and you follow the necessary on-page SEO practices, a secondary keyword or two won't make much difference.
3 Examples of secondary keywords in SEO
Now that you've gotten the gist of secondary keywords, let's have a look at some examples.
We'll provide sample content topics for different industries with primary and secondary keywords, including synonyms and long-tail keywords.
Secondary keywords for healthcare
Topic: Proven ways to build muscle quickly
Primary keyword: build muscle
Secondary keywords:
- building muscle
- muscle growth
- build muscle mass
- muscle gain diet
- gain muscle fast
- how to gain muscle mass
- build muscle as a woman
Secondary keywords for finance
Topic: Money management tips everyone should follow
Primary keyword: money management tips
Secondary keywords:
- managing money
- financial management tips
- personal money management tips
- manage personal finances
- tips for managing money
- money management plan
- how to manage your money
Secondary keywords for e-commerce
Product page/topic: Sunscreen moisturizer
Primary keyword: sunscreen moisturizer
Secondary keywords:
- sunscreen with moisturizer
- spf moisturizer
- moisturizer with spf
- face moisturizer spf
- best face moisturizer with spf
- moisturizer sunscreen for dry face
- daily moisturizer with sunscreen
Key takeaways
- Secondary keywords are search terms that specify and support the primary keyword, helping search engines understand the context behind your content. They can be synonyms or long-tail variations of the primary keyword.
- By uncovering secondary keywords, you can write relevant content that ranks for a broader range of search terms. A single article can target several search queries at once, which consolidates your SEO efforts.
- The easiest way to find secondary keywords is to Google the primary keyword. You can then check Google Autocomplete, PAA, and Related searches for keyword ideas.
- For a more comprehensive keyword research strategy, you can use various tools like AnswerThePublic, Google Keyword Planner, and Surfer's Content Editor.
- Secondary keywords must be included in your content naturally. Awkward keyword placement negatively impacts your content's quality and user experience, which harms the piece's search ranking.
- You can include secondary keywords throughout the content's body, subheadings, image alt text, and sometimes meta descriptions. Keep in mind that the primary keyword is still more important, so it must be added to the URL, metadata, and the main heading.
- Keyword stuffing damages your content's value in the eyes of both users and search engines. Pay close attention to keyword density while writing, and feel free to exclude keywords you can't fit in naturally (Google will still be able to index and rank your content for the primary keyword).
