hapax legomenon
noun /ˌhæpæks ləˈɡɒmənɒn/
/ˌhæpæks ləˈɡɑːmənɑːn/
(plural hapax legomena
(linguistics) /ˌhæpæks ləˈɡɒmənə/
/ˌhæpæks ləˈɡɑːmənə/
)- a word or phrase that is recorded as having been used only onceWord Originmid 17th cent.: Greek, ‘a thing said once’, from hapax ‘once’ and the passive participle of legein ‘to say’.