A round, low-crowned felt hat; a wideawake. B. H. Chamberlain. [1913 Webster]
"Little acquiesced, and Ransome disguised him in a beard, and a loose set of clothes, and a billicock hat." [Webster 1913 Suppl.]

bad hat, billycock, bishop's hat, bowler hat, brass hat, campaign hat, cavalier hat, church hat, cocked hat, cowboy hat, derby hat, dress hat, felt hat, fur hat, gainsborough hat, hard hat, hat, hat shop, hat trick, high hat, iron hat, mexican hat, old hat, opera hat, panama hat, picture hat, pith hat, plug hat, porkpie hat, safety hat, service hat, shovel hat, silk hat, slouch hat, straw hat, sun hat, ten-gallon hat, tin hat, top hat, woman's hat