décerveler

A rare, mostly literary and pejorative verb — historically "to extract the brains of" (an animal, or in Alfred Jarry's grotesque Ubu Roi, where the "Machine à décerveler" literally removes people's brains) — now used figuratively for reducing someone to a docile, thoughtless follower (une propagande qui décervelle les foules).

• Dans Ubu Roi, la Machine à décerveler élimine les opposants du roi. — In Ubu Roi, the Brain-Extracting Machine eliminates the king's opponents.
• Cette propagande vise à décerveler les foules plutôt qu'à les informer. — This propaganda aims to turn the crowds into mindless followers rather than inform them.
• On l'accuse de faire une télévision qui décervelle son public. — He's accused of making television that turns its audience's brains to mush.

Almost always figurative and pejorative in modern use (to dumb someone down, to make them docile) — a learner using only the literal medieval sense (to physically remove someone's brain) would sound archaic outside a literary or historical discussion.

• book Ubu Roi — Alfred Jarry's 1896 absurdist play features the "Machine à décerveler" ("brain-extracting machine"), a grotesque device Père Ubu uses on his enemies, celebrated in the play's grim "Chanson du décervelage."