Puzzles or tricky questions asked as a game, where you have to guess the answer, or to fill with holes.
From Old English "rǽdels" meaning opinion or conjecture, related to "rǽdan" (to advise or guess). Originally meant to speak in riddles, and later meant a puzzle.
Riddles predate writing—they were how oral cultures preserved wisdom and tested cleverness before books existed, and they appear in almost every ancient mythology from Oedipus to Anglo-Saxon epics!
Complete word intelligence in one call. Free tier — 50 lookups/day.