| Definition -
(1) An ambiguously structured clause or sentence that can be interpretted in multiple ways.
(2) A figure of speech where the ambiguity is purposely created by using an ambiguously structured clause or sentence.
Example - "I once shot an elephant in my pajamas. How he got in my pajamas I'll never know."
(Groucho Marx, Animal Crackers)
Etymology - The word derives from the Greek amphibolia, ambiguity + logia, speech.
Oxford English Dictionary - Its first citation for sense (1) is from circa 1374:
"For goddes speken in amphibologies, And for o soth, they tellen twenty lyes."
(Chaucer Troylus iv. 1406)
Its first citation in sense (2) is from 1589:
"Such ambiguous termes they call Amphibologia, we call it the ambiguous, or figure of sence incertaine."
(Puttenham Eng. Poesie (Arb.) 267)