LSI Keywords: An evolution in on-page SEO.
As Google's algorithm "evolves", and gets more intelligent, it is better able to determine what your webpage is about - and one of these improvements is through LSI.
LSI, an acronym for Latent Semantic Indexing, is an indexing and retrieval method that uses a mathematical technique called singular value decomposition (SVD) to identify patterns in the relationships between the terms and concepts contained in an unstructured collection of text. (source)
Great... Another definition that doesn't make any sense unless I have 4 PhDs.
So, let me put it another way that's easier to grasp:
Latent semantic indexing is an information retrieval concept used by search engines to uncover & understand how content & terms content work together to create meaning - even if they do not share synonyms or keywords.
Still a bit confusing, but probably starting to make a little more sense, yes?
Keep reading and you will be the LSI master by the end of this.
So, we know that search engines are smart enough to identify & understand the context of your content, and the synonyms that are related to your keywords.
But LSI is not this simple - a lot of people think LSI keywords are just simply synonyms, but that is not correct (otherwise we would just call them synonym keywords).
The simplest definition for LSI keywords I can give is that they are just words frequently found together because they have a similar context.
Almost like...complementary words.
It is a way for search engines to fully understand what a page is about when there might otherwise be confusing.
Remember back in the day when you would Google something like "Apple" (hoping to find some nutrition information about your favorite fruit) only to be given a page of results about this new thing called an iPod?
Well, Latent Semantic Indexing helps solve that problem.
Here is a great example:
In Google's earlier iterations (the "easy to SEO" Google) the algorithm would determine what a page was about solely by reading keywords.
You could put your keyword on the page 1000 times and almost instantly rank for it (called keyword stuffing - don't do this now, it will get your website penalized and it reads like total dog shᴉt)
This might have worked back in 2011, but since the release of 2 major algorithm updates: Hummingbird & RankBrain, Google has become significantly better at understanding context & meaning of a webpage with regards to a user's search query, by understanding the relationship of related words & phrases found in the content.
Here is an example of keywords stuffing.
A page about "chiropractic treatment" that uses the word chiropractic 57 times, and treatment 39 times (in a fairly short article I might add).
If Google saw a keyword used over and over again it thought "well this page is clearly super relevant to this term it talks about is soooo much".
But, we all know this isn't how people talk. And Google knows that. So with the introduction of Latent Semantic Indexing, the algorithm can now use OTHER words (those complementary words we mentioned earlier) to understand what a page is about.
Now, with LSI technology, Google can read a page's content and understand the overall topic/context.
LSI Keywords allow Google to determine the context & topic of your page.
And when Google can confidently understand what your page is about it will trust you more -thus giving you credit for being relevant for that topic and reward you with an SEO boost.
Certain groupings of words are seen together in predictable patterns.
Google sees these patterns, and begins to understand more about the intent & meaning behind a user's search query - instead of just relying on matching up keywords to determine relevance, it can match up intent with meaning.
This allows Google to improve the match between the search query (what someone searches for) and the result (the resource Google provides to answer that query).
Starting to sound like robots can think like humans.
There are some great methods & keyword tools that can help you find LSI Keywords.
Our Top Recommendations For Finding LSI keywords:
Using Google to find LSI keywords is a great way to get started.
For example, let's say you are writing about asthma. Some of the things you might want to cover are symptoms, treatments, diagnosis, and other common words usually mentioned when discussing the condition.
How do you know to use all these? Well, just Google your and look through the SERP!
You can also scroll down the bottom and use the "Searches related to" area:
Remember, we are trying to find things that people generally associate with and search for information about when understanding how we can comprehensively cover a topic (and get our LSI keywords into our content).
Using competitors to find LSI keywords is an amazing "SEO hack".
You are basically relying on the fact that Google already trusts the people on Page 1 - so why not reverse engineer their success?
It works like magic in SEO (and most things digital marketing as well).
1. Enter your seed keyword into Ahrefs keywords explorer:
2. Scroll down to see the "SERP Overview" (aka who is ranking at the top) & click on the keywords (its a number) to see all the keywords that their article is showing up for:
3. Scroll through their keywords to get ideas of more keywords that you should include in your article (or larger content strategy):
You can see from the screenshot above that this ONE article that is ranking for "asthma" is also ranking for 1,595 other related keywords in the USA alone!
That is the power of the LSI.
Simple to use, just enter your keyword into the search box, and the comb through the results!
Twin Word is a super cool tool that gives you a little "web" of LSI keywords you can include in your research:
1. Search your keyword:
2. Get results
Semantic Link is another great tool for finding LSIs.
You use LSI keywords just like you do any kind of on-page SEO optimization - naturally throughout important places in the content:
Choose the right keywords is really the foundation of doing this right.
Start with the keyword tools, but most importantly use your brain.
These tools are not always correct, and sometimes pull up weird keywords that aren't actually something you want to include, just use common sense to weed out the weird ones.
The easiest way to properly use LSI keywords is just to be natural.
Do your research, understand your topic, outline your article - and start writing.
Don't worry too much about placing these all the LSIs in strategic places so much - just write. In the end you can go back through and see if there are opportunities to naturally slide some more terms into the important places in that you know about from learning about on page seo.
If you have any questions about what you read in this article, or if you just want help getting it done, we highly recommend you join the free SERP University Group, where we are dedicated to helping you with all your SEO & Digital Marketing questions.
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