Google bowling is a reverse SEO, in which external link factors are measured that are used to decrease the page rank of its competitor by black hat seo techniques.
Google Bowling in SEO is a Black Hat SEO technique in which we bring down the website of our competitor's using illegal SEO techniques in order to improve the website rank on our search engines.
The process of keyword stemming involves taking a basic but popular keyword pertaining to a particular website and adding a prefix, suffix, or pluralization to make the keyword into a new word.