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hatband

American  
[hat-band] / ˈhætˌbænd /

noun

  1. a band or ribbon placed about the crown of a hat, just above the brim.

  2. a black band similarly worn as a sign of mourning.


hatband British  
/ ˈhætˌbænd /

noun

  1. a band or ribbon around the base of the crown of a hat

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of hatband

late Middle English word dating back to 1375–1425; hat, band 2