'bandersnatch' originates from Lewis Carroll (English), specifically coined as a nonce word in the poem 'Jabberwocky' (published in Through the Looking-Glass, 1871); it appears to be a fanciful compound built around the element 'snatch' (to seize) and a front element 'bander-' possibly echoing 'bandit' or simply invented for sound.

'bandersnatch' was coined by Lewis Carroll in 1871 in the poem 'Jabberwocky' and later adopted and reused in various fantasy works, games, and popular culture (e.g., role‑playing games, novels, and the TV episode title), eventually becoming the established modern English nonce/name 'bandersnatch'.

Initially it referred specifically to a fanciful creature in Carroll's poem; over time the term broadened to include a figurative sense for any unpredictable or dangerous person/thing and to serve as a proper name in later works.