go off at score

idiomatic

(idiomatic) Of a horse, to break suddenly into a gallop. / (idiomatic) Suddenly to say or do something impetuous.

Japanese Meaning

馬が突然ギャロップで走り出すこと / 突然、軽率な発言や行動をすること

When the starter pistol cracked, the mare began to go off at score and sprinted ahead of the field.

スターティングピストルが鳴ると、その牝馬は突然一気に駆け出して、群れを引き離して先頭に立った。

Sense（1）

(idiomatic) Of a horse, to break suddenly into a gallop.

Sense（2）

(idiomatic) Suddenly to say or do something impetuous.

goes off at score

（ present singular third-person ）

going off at score

（ participle present ）

went off at score

（ past ）

gone off at score

（ participle past ）