Tight rein on, a

What is Tight rein on, a?

Tight rein on, a definition and meaning on Dictionary terms:
Strict control over, as in We told them to keep a tight rein on spending for the next year. This expression alludes to the narrow strap (rein) attached to a bit and used to control a horse’s movements. Rein has been used to refer to any kind of restraint since the first half of the 1400s.


reference: www.dictionary.com/browse/tight-rein-on–a