Bridle

Bridle-n
1-a set of leather straps fitted to a horse's head and incorporating the bit and the reins
2-something that acts as a control or restraint

v
1-(vt) to provide a horse with a bridle
2-(vi) to react with slight anger or indignation, sometimes by rearing the head
3-(vt) to show restraint in expressing a feeling or control or in curbing something

Synonyms
bristle
get angry
become annoyed
become indignant
prickle
get your hackles up