babel has 1 distinct synonym spread across 1 of its 2 senses. Each sense below keeps its own list, because a synonym belongs to a meaning and not to a word: swapping one sense's substitute into another sense's sentence is how a thesaurus makes writing worse. WordNet records no antonym for it — antonymy is a relation between word forms rather than concepts, so it is deliberately sparse.
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.
(Genesis 11:1-11) a tower built by Noah's descendants (probably in Babylon) who intended it to reach up to heaven; God foiled them by confusing their language so they could no longer understand one another
a confusion of voices and other sounds
Synonyms, antonyms and the broader and narrower relations for babel come from Princeton University’s WordNet. Full sources and licences.