Keyword Stuffing
Definition: Keyword stuffing is the act of plugging an abundance of the same keywords and keyword phrases into your website body content and Meta tags in an attempt to artificially boost your rank in SERPs.
Just as stuffing your face with too much food isn't a bright idea, keyword stuffing your webpages is a big no-no. Not only will you frustrate readers with your redundancy, you stand a good chance of being labeled a spammer by top search engines, and your page rank could decrease as a direct result.
Implementing keywords throughout your page content and Meta tags is important, but do yourself and your readers a favor- stick to tasteful moderation!