1 (often reins) for controlling a horse
VERB + REIN hold Can you hold the reins for a minute? | gather (up), pick up Sean gathered up the horse's reins. | grab (at), pull on She pulled sharply on the reins. | give/hand sb, let go of | lengthen, shorten
PREP. on a ~ She had the horse on a long rein.
2 the reins: being in control/the leader of sth
VERB + REIN hold It's the Treasury that effectively holds the reins. | grasp, take up The vice-president was forced to take up the reins of office. | hand over
PHRASES the reins of government/office/power