preen

PREEN, n. A forked instrument used by clothiers in dressing cloth.

PREEN, v.t. To clean, compose and dress the feathers, as fowls, to enable them to glide more easily through the air or water. For this purpose they are furnished with two glands on their rump, which secrete an oily substance into a bag, from which they draw it with the bill and spread it over their feathers.