Evasive, wary, or unwilling to commit to a clear position; secretively cautious.
From 'cage' or possibly circus/carnival slang, gaining popularity in American English by the 1890s. Possibly related to the behavior of caged animals or the literal cages around early basketball courts.
Nobody knows for certain where 'cagy' came from, but it perfectly captures that feeling when someone is answering you without actually answering—it's a word that feels like it describes behavior rather than stating facts.
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