When it comes to search engine marketing, there may be no larger misnomer, no more archaic term than the ubiquitous keyword. In my view, there should be an official migration to the more accurate term keyphrase, but for now I will be forced to use what I consider to be an inaccurate term. My frustration with this term is that it quite simply implies a single word, which is rarely the strategy that we employ when doing keyword research and selection in the service of PPC and SEO campaigns.
Your SEO keywords are the keywords and phrases in your web content that make it possible for people to find your site via search engines. A website that is well optimized for search engines "speaks the same language" as its potential visitor base with keywords for SEO that help connect searchers to your site. Keywords are one of the main elements of SEO.