The Spanish word 'buchón' comes from 'buche' (meaning 'crop of a bird' or 'mouthful') combined with the augmentative suffix '-ón', literally meaning 'having a large crop'. The word 'buche' itself derives from Latin 'buccula', meaning 'small mouth' or 'blister', which is a diminutive form of Latin 'bucca' meaning 'mouth' or 'cheek'. The evolution shows an interesting semantic shift from words relating to the mouth and cheeks to specifically referring to a bird's crop or gullet.

A simpler related Spanish word is 'buche', which refers to a bird's crop (the pouch in a bird's throat where food is stored) or can mean 'mouthful' in general usage. This connection makes the meaning of 'buchón' more intuitive, as it essentially means 'having a large buche' or 'having a prominent crop'.

While there aren't many common English words directly related to 'buchón', we can find some scientific or anatomical terms that share the Latin root 'bucca'. For example, 'buccal' is a medical term relating to the cheek or mouth (as in 'buccal cavity'). The word 'debouch', meaning 'to emerge or empty into' (as a river into the sea), also comes from the same Latin root, though it entered English through French.