v. & n.
v. 1 intr. wrinkle one's brows, esp. in displeasure or deep thought. 2 intr. (foll. by at, on, upon) express disapproval. 3 intr. (of a thing) present a gloomy aspect. 4 tr. compel with a frown (frowned them into silence). 5 tr. express (defiance etc.) with a frown.
n. 1 an action of frowning; a vertically furrowed or wrinkled state of the brow. 2 a look expressing severity, disapproval, or deep thought. frowner n. frowningly adv.
[ ME f. OF frongnier, froignier f. froigne surly look f. Celt. ]