Positioning as in "positioning of a web site" refers to the ability to promote the visibility of a site in the search engine results. 

Positioning refers to where a web site or web page is ranked on a Search Engine Results Page (SERP). Web sites or pages that are appropriately optimized and highly relevant to the searcher's query typically earn a higher position in the organic search results. For PPC search results, bid management is an additional component that affects positioning.