desplumar

Literally to pluck the feathers off a bird — desplumar un pollo (pluck a chicken). Just as commonly, it's a vivid colloquial idiom for fleecing someone out of their money: lo desplumaron en el casino, built on the image of a bird losing every one of its feathers the way a swindled person loses all their cash.

• Desplumamos el pavo antes de meterlo al horno. — We plucked the turkey before putting it in the oven.
• Lo desplumaron jugando al póker toda la noche. — They fleeced him playing poker all night.
• Cuidado con esa tienda, te desplume sin que te des cuenta. — Watch out for that store, it'll fleece you without you noticing.

Missing the figurative "swindle/fleece" sense and only recognizing the literal bird-plucking meaning — in everyday conversation about money or gambling, the figurative sense is usually the one intended.

• expression "Te van a desplumar" — A widely used fixed idiom meaning "they're going to fleece/rob you blind" — dictionaries including Cambridge and Collins confirm this figurative "swindle someone out of their money" sense as a standard idiomatic use of desplumar, built on the image of plucking a bird bare.