eve has 3 distinct synonyms spread across 1 of its 4 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.
(Old Testament) Adam's wife in Judeo-Christian mythology: the first woman and mother of the human race; God created Eve from Adam's rib and placed Adam and Eve in the Garden of Eden
the day before
“he always arrives on the eve of her departure”
the period immediately before something
“on the eve of the French Revolution”
the latter part of the day (the period of decreasing daylight from late afternoon until nightfall)
“he enjoyed the evening light across the lake”
Synonyms, antonyms and the broader and narrower relations for eve come from Princeton University’s WordNet. Full sources and licences.