bristle

Concise Oxford English Dictionary © 2008 Oxford University Press:
bristle /ˈbrɪs(ə)l/

▶noun a short, stiff hair on an animal's skin or a man's face.

■ a stiff animal hair, or a man-made substitute, used to make a brush.

▶verb

• 1 (of hair or fur) stand upright away from the skin, as a sign of anger or fear.

• 2 react angrily or defensively.

• 3 (bristle with) be covered with or abundant in.

– derivatives
bristly adjective.

– origin ME: from OE byrst (of Gmc origin) + -le1.