A
wattle is a fleshy
caruncle hanging from various parts of the head or neck in several groups of birds and mammals. A
caruncle is defined as 'A small, fleshy excrescence that is a normal part of an animal's anatomy'.
[1] Within this definition, caruncles in birds include wattles,
dewlaps,
snoods and earlobes. Wattles are generally paired structures but may occur as a single structure when it is sometimes known as a
dewlap. Wattles are frequently organs of
sexual dimorphism. In some birds, caruncles are erectile tissue and may or may not have a feather covering.