Reeker is a derogatory term used for someone who has a strong unpleasant body odor. To avoid using such a rude term, there are several synonyms one could use. Some possible options include "stinker," "odoriferous," "malodorous," "funky," "smelly," "pungent," "rank," "foul," and "stinky." Each of these substitutes can be used to describe someone with bad body odor without being as offensive or hurtful. By using these synonyms, we can remain polite and respectful while still getting our point across about someone's unpleasant body odor.