www.alphadictionary.com

an ornament (as a rosette) usually worn on a hat as a badge

So how does this relate to the root of cock (tap), see cocktail by Herr Goodword.

I gather that it does not relate to tap, but to the male farm bird also called a cock. Etymonline tells us that cockade is from the 18th century and began life as cockard, from French cocarde, feminine of cocard arrogant, strutting, from coq cock.

In case anyone wants a refresher on our Good Dr.'s cocktail, you may find it here.

We had an older forester in Lions Club awhile back who liked to obsess on the rarity of the red cockaded woodpecker. Were he still alive, he would be happy to note several informed reports of sightings in Arkansas just north of the LA line.