The Collaborative International Dictionary of English v.0.48:
Beetle-browed \Bee"tle-browed`\, a. [OE. bitelbrowed; cf. OE. bitel, adj., sharp, projecting, n., a beetle. See Beetle an insect.] Having prominent, overhanging brows; hence, lowering or sullen. [1913 Webster] Note: The earlier meaning was, "Having bushy or overhanging eyebrows." [1913 Webster]WordNet (r) 3.0 (2006):
beetle-browed adj 1: sullen or unfriendly in appearance [syn: beetle-browed, scowling]