As a nomenclatural note, even obvious term variants like "pictures" (plural) and "picture" (singular) would be treated as different search terms by a dumb computer, so we also include these types of relationships within our umbrella of synonyms. Pictures/picture are typically called stemming variants, which refers to the fact that they share the same word stem, or root. The same systems that need to understand that "pictures" and "photos" mean the same thing also need to understand that "pictures" and "picture" mean the same thing. This is something that is even more obvious to a human but is also still a difficult task for a computer. An example of how this is difficult are the words "animal" and "animation," which share the same stem and etymology, but don't mean the same thing in standard use. Another tricky case that is very dependent on the other words in the query is "arm" vs. "arms." Arms might seem like the plural of arm, but consider how it might be used in a search: [ arm reduction ] vs. [ arms reduction ]. Google search is smart enough to know that the former is about removing fat from one's arm, and the latter is about reducing stockpiles of weaponry, and that arm/arms are dangerous synonyms in that case because they would change the meaning. These subtle differences between words that seem related is what makes synonymy very hard to get right.Here are some other examples of synonyms we thought were interesting: song words ], "lyrics" is bolded for "words". what state has the highest murder rate ], "homicide" is bolded for "murder". himalayan kitten breeder ], Google knows that "cat breeder" is the same as "kitten breeder". dura ace track bb axle njs ], Google knows that "bb" here means "bottom bracket". software update on bb color id ], "blackberry is bolded for "bb". bb cream dark ], Google knows here that bb means "blemish balm". southeastern usa bb fitness & figure ], "bodybuilding" is bolded for "bb."Lastly, language is used with as much variety and subtlety as is present in human culture, and our algorithms still make mistakes. We flinch when we find such mistakes; we're always working to fix them. One of the best ways for us to discover these problems is to get feedback from real users, which we then use to inspire improvements to our computer programs. If you have specific complaints about our synonyms system, you can post a question at the web search help center forum or you can tweet them with the hash tag #googlesyns. You can also turn off a synonym for a specific term by adding a "+" before it or by putting the words in quotation marks.