at the drop of a hat

Prepositional phrase

idiomatic informal

(informal, idiomatic) Without any hesitation; instantly.

Japanese Meaning

ためらうことなく、すぐに / 瞬時に、即刻に / 即座に、ためらいなく

She would volunteer to help at the drop of a hat, even if it meant rearranging her entire weekend.

彼女は週末を全部入れ替えることになっても、何のためらいもなく手伝うだろう。

Sense（1）

(informal, idiomatic) Without any hesitation; instantly.

We're expected to just do it at the drop of a hat.