A complicated or strange-looking machine or device, usually invented for a specific purpose, often used humorously.
From 'contrap-' (possibly from Latin 'contra-' meaning against, plus 'trap') or possibly an invented word combining elements. First appeared in American English around 1800s, likely an Americanism.
Nobody knows for sure where 'contraption' came from—it might be American slang that combined several sounds, which makes it perfect because 'contraption' sounds exactly like a Rube Goldberg machine would sound: clunky and made-up.
Complete word intelligence in one call. Free tier — 50 lookups/day.