the.com/tricorn hat

A hat that folds its brim three times so you can doff it without losing an eye.

means A hat with its brim turned up and pinned into three points, popular menswear from roughly the 1700s through the early 1800s.

from From Latin tri- ('three') plus cornu ('horn' or 'corner'), so literally 'three-cornered.' The style itself grew out of simpler cocked hats whose wide, floppy brims got pinned up on three sides — partly for fashion, partly to keep rain off the face while still leaving a sharp silhouette. The word 'tricorn' is actually a later label; people of the era mostly just called it a 'cocked hat.'

origin
started as a practical rain gutter for cavalry hats
peak era
18th century, worn by pirates and presidents alike
name truth
three corners, zero relation to actual unicorns
decline cause
replaced by the taller bicorn, worn sideways for ease
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