the.com/synonym

a word that means the same thing, but somehow always feels classier at parties

means A word that has the same or nearly the same meaning as another word in the same language.

from From Greek 'syn-' meaning 'together' or 'same' and 'onyma' (a dialectal form of 'onoma') meaning 'name' — so literally a 'same name.' That 'onoma' is a deep cousin of Latin 'nomen' and English 'name' itself. The word reached English through Latin 'synonymum,' and you'll spot the same '-onym' family lurking in 'antonym,' 'homonym,' and 'pseudonym.'

greek roots
From syn (together) and onoma (name)
never identical
True perfect synonyms barely exist in any language
register matters
Buy and purchase mean the same, feel different
thesaurus fuel
Roget's 1852 book made synonym-hunting a sport
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