at the helm
IN CHARGE, in command, in control, responsible, in authority, at the wheel, in the driving seat, in the saddle, holding the reins, running the show, calling the shots

[TahlilGaran] Dictionary of Contemporary English ▲

at the helm
at the helm (of (something))
in control.
He resigned and left the company last July after two years at the helm.

Etymology: based on the literal meaning of helm (= the handle or wheel that controls the direction in which a ship travels)

[TahlilGaran] English Idioms Dictionary ▲