KEI (Keyword Effectiveness Index)
The KEI (keyword effectiveness index) calculates the ratio of the number of times a particular keyword phrase is searched for per month in a search engine along with the number of competing web pages and returns the value of which keyword phrases are the most valuable for your keyword research campaign. This is similar to Keyword Difficulty.
Keyword Cannibalization
When two or more web pages of your website rank for the same keyword phrase this causes something called keyword cannibalization where your website is competing against itself. This can have a negative role on your website rankings and traffic because it will lower your CTR (click-through rate), lower the authority of your website, and as a result lower the conversation rate of your website. The best practice is to silo your content into hub pages (parent pages) and sub-categories (children pages) of your content.
A possible plus can occur from this though. You may end up ranking twice in the SERPs for the same keyword phrase which gives you more real estate in the SERPs (search engine results pages).
Keyword Density
The keyword density is the ratio of how many times a keyword phrase is mentioned on a web page compared to the number of words that are on the page. In the past, black-hat SEO people used Keyword Stuffing to increase their chances of ranking for that keyword phrase. But today, the search engines already know of this trick and you can get penalized for using this black-hat technique.
Keyword Difficulty
SaaS (software as a service) ranks how difficult it is to rank for a particular keyword phrase using different metrics such as data from Google Ad Planner, how many websites use this keyword phrase, how many backlinks use this keyword phrase as an anchor text, domain age, use of the keyword phrase in the website content, etc. to display a number from 1 to 100 on how difficult it would be to rank for this keyword phrase for your website.
Keyword Research
Keyword research is the act of examining a particular keyword phrase to find out how many times it is searched for per month, how strong the competition is for that keyword phrase, how difficult it is to rank for that keyword phrase and find alternatives to that keyword phrase that you can use for your website if it is too competitive. A more detailed description of keyword research can be read by following the link.
Keyword Phrase/Search Phrase
The old term used to be just Keyword where you tried to rank for a keyword but everything evolved beyond that and the correct phrase now is keyword phrase which is a string of keywords. A keyword phrase is typed into the search engine by a user to try and find a specific website and the goal of the website is to have its website pop up close to the top of the SERPs (search engine results pages) while it is the search engines goal to display the most relevant websites near the top of the SERPs that match the keyword phrase used.
Keyword Prominence
The position of the keyword phrase on a page is the keyword prominence. The higher on the page (excluding the navigation) the better the chance it is to rank for that keyword phrase if the page relates to the subject matter of that keyword phrase.
Keyword Stemming
Google’s ability to understand other variations of a base word is called Keyword Stemming. This refers to different longer variations of a keyword. For example, the word cook is the cooker, cooking, cooks, cooked, etc. When you want to rank for the keyword cook on the page it is a good idea to do keyword stemming and include the keywords cooker, cooking, cooks, cooked, etc.
Keyword Stuffing
The act of repeating a particular keyword phrase numerous times on a page to try and rank for it is called keyword stuffing. This relates to the term Keyword Density which has the ratio of the number of times a keyword phrase is mentioned on the page compared to the number of words on that page. Google has changed its algorithm a long time ago to deter this black-hat technique.
Knowledge Box
This is the box of information that is shown in the SERPs (search engine results pages) when someone does a particular search. A lot of time this results in zero-click results that prevent people from visiting your website because the information that they seek is displayed in the knowledge box.
Knowledge Graph
The Google Knowledge Graph is a knowledge base used by Google and its services to enhance its search engine results with information gathered from a variety of sources. The information is presented to users in an infobox next to the search results.
KPI (Key Performance Indicator)
The Key Performance Indicator (KPI) is a measurement used by businesses to see how effective changes to the marketing of a website affect the business’s goals.