E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
The face, is allied to the Latin caput, the head; Greek ε-o, Anglo-Saxon ceafel, the snout; in the plural, the cheeks. We talk of a pigs chap.
The Latin cap-ut gives us the word chap, a fellow or man; and its alliance with chop gives us the term chapped hands, etc. Everyone knows the answer given to the girl who complained of chapped lips: My dear, you should not let the chaps come near your lips.
Down in the chopsi.e. down in the mouth in a melancholy state; with the mouth drawn down. (Anglo-Saxon, cealf, the snout or jaw; Icelandic, kiaptr.)