The word "hummer" can have several synonyms depending on the context of its usage. In the sense of a hummingbird, it can be replaced by words like "chirper," "flutterer," or "buzzard." When the term is used for a vehicle, it can be substituted by "SUV," "all-terrain vehicle," or "off-roader." In terms of music, a hummer can be replaced by "crooner," "warbler," or "singer." In slang language, "hummer" can signify oral sex, and thus can be substituted by "blowjob," "fellatio," or simply "oral." In conclusion, understanding the context of the word "hummer" is important to determine appropriate synonyms.