1 (of a bird) tidy (the feathers or itself) with its beak.
2 (of a person) smarten or admire (oneself, one's hair, clothes, etc.).
3 (often foll. by on) congratulate or pride (oneself).
Phrases and idioms:
preen gland a gland situated at the base of a bird's tail and producing oil used in preening.
Derivatives:
preener n.
Etymology: ME, app. var. of earlier prune (perh. rel. to PRUNE(2)): assoc. with Sc. & dial. preen pierce, pin
Useful english dictionary. 2012.