The Collaborative International Dictionary of English v.0.48:
Broad-brimmed \Broad"-brimmed`\, a. Having a broad brim. [1913 Webster] A broad-brimmed flat silver plate. --Tatler. [1913 Webster]WordNet (r) 3.0 (2006):
broad-brimmed adj 1: (of hats) having a broad brim