Plural of 'eve', meaning the day or evening before an important event, or the plural of the name Eve.
From Old English 'æfen' (evening), which traces to Proto-Germanic 'abandiz'. 'Eve' shortened to mean 'the evening before', especially religious holidays like Christmas Eve and New Year's Eve.
Christmas Eve and New Year's Eve are so culturally famous that most people don't realize 'eve' originally just meant any evening—the religious calendar made certain 'eves' more important than others!
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