WordNet records no synonym and no antonym for cabin. 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.
small room on a ship or boat where people sleep
a small house built of wood; usually in a wooded area
Synonyms, antonyms and the broader and narrower relations for cabin come from Princeton University’s WordNet. Full sources and licences.
the enclosed compartment of an aircraft or spacecraft where passengers are carried
confine to a small space, such as a cabin