Google just blogged about synonyms as they related to searcher intent. They provide several examples of how a concept as simple as a synonym complicate natural language processing. This also brings up some important recommendations for site owners with respect to SEO.
Prospective customers type in all kinds of variations on your most obvious keywords (hence the need for keyword research). Often they make use of synonyms, some common, some not. These variations often represent less competitive opportunities for high search engine rankings if you can incorporate those synonyms into your website. In particular:
- Use common variations within your existing copy rather than using the same phrase repeatedly. (This also tends to make long blocks of text more readable.)
- Develop pages that specifically focus on each of the most common and valuable synonyms.
- If there are enough synonyms and industry-specific terms, consider developing a glossary of terms.
- Find opportunities to talk about the synonyms, such as a blog post or article that talks about how synonyms may actually be somewhat different or whose similarity is up for debate (e.g. SEM vs. Search Engine Advertising).