The Collaborative International Dictionary of English v.0.48:

earflap \earflap\ n.
   one of two flaps attached to a cap to keep the ears warm. On
   some hats the earflaps may be adjusted or tied to the top of
   the hat, and lowered when needed in colder weather.

   Syn: earlap.
        [WordNet 1.5 +PJC]