This is word specifically use for search engine ranking and postions about your keyword
SERP = Search Engine Results Page. You might say SERPs are what SEO is all about. The fundamental goal of SEO is, for a given search term/keyword, to achieve a top ranking on search engines with your website. You want your site to be at the top of the first SERP.
SERP stands for Search Engine Rank Page. SERP is a the listing of results given by the search engines like Google or Yahoo as a response to a user's inquiry. The words typed in the search bar are called keyword query. Results will display the title or partial description of a website page where the keywords query are. SEO's main goal is to increase a website's rank or page results. SERP is useful in SEO because it will serve as an evaluation if your are really hitting the mark in SEO.