WordNet records no synonym and no antonym for bathe. It is the only member of each of its synsets, which is common for technical, taxonomic and single-sense vocabulary — there is no other English word that means the same thing. The broader and narrower terms below are the useful relations in that case.
Counts are distinct word forms across every sense. A synonym that appears under three senses is counted once here and shown three times below, under each sense it belongs to.
suffuse or envelope with something
“The room was bathed in sunlight”
Synonyms, antonyms and the broader and narrower relations for bathe come from Princeton University’s WordNet. Full sources and licences.
swim for pleasure or recreation
the act of swimming for pleasure or recreation
“the Englishman said he had a good bathe”