To make a clicking noise with a sucking action of the tongue, to express disapproval or impatience, urge on a horse, etc.

To click one's tongue.

Alternative form of onside

(US) Alternative form of at short notice

(archaic) To alter the direction of attacking; to take a new approach to try to achieve an objective.

Not on one's guard; inattentive to possible hazards and thus vulnerable.

Placed in a situation where one's best behaviour is necessary or advisable.

(idiomatic) To insist on something firmly or with stubbornness.

To excite remorse in someone by returning good for evil.

Alternative form of on the verge of / Alternative form of on the edge