Look up hackle in Wiktionary, the free dictionary.
The hackles are the long, fine feathers which are found on the backs of certain types of domestic chicken. They are often brightly coloured, especially on roosters. These feathers are often used as fly lures.
The term can also apply to the erectile hairs along the back of the neck of an animal, especially of a dog. Hackles are usually used as visual warnings to other animals or threats. The animals will raise their hackles up to threaten another animal. Dogs may raise their hackles as a sign of aggressive behavior to show their dominance over conspecifics. Raised hackles is a behavior that can also be observed in dominant wolves who show aggression towards subordinate wolves.
^Svartberg, Kenth; Forkman, Björn (October 20, 2002). "Personality traits in the domestic dog (Canis familiaris)". Applied Animal Behaviour Science. 79 (2): 133–155.|access-date= requires |url= (help)
^Barrett, edited by James Serpell ; pencil drawings by Priscilla (1999). The Domestic dog : its evolution, behaviour, and interactions with people (Repr. ed.). Cambridge, England: Cambridge University Press. p. 118. ISBN9780521425377.|access-date= requires |url= (help)