"Hold your horses", sometimes said as "Hold the horses", is an English-language idiom meaning " wait, slow down". The phrase is historically related to horse riding or travelling by horse, or driving a horse-drawn vehicle. A number of explanations, all unverified, have been offered for the origins of the phrase, dating back to usage in Ancient Greece.
The saying is typically used when someone is rushing into something. "Cool your jets" is an essentially identical idiom. However it also has a more literal meaning and in certain circumstances is the preferred idiom to use. "Hold your horses" literally means to keep your horse(s) still, not to be confused with holding them in a stable. Someone is to slow down when going too fast, [1] or to wait a moment, or to be more careful, [2] or to be patient before acting.
It is usually followed up with an explanation to demonstrate why you should wait. [3] For example, "Hold your horses, we have not won yet, so don't start celebrating." [4] and "Hold your horses, you haven't thought about this yet" or "Hold your horses, you might find a better one for the same price in another store" [5] or "Hold your horses. We're almost there." [2]
There are several sources documenting the usage of "hold your horses"
If someone tells you to hold your horses, you are doing something too fast and they would like you to slow down.
Usage notes: usually used as an instruction, as in the example 'Hold your horses, Colin, I'm working as fast as I can!'
But Antilochus turned aside his single-hooved horses, and drave on outside the track, and followed after him, a little at one side. [425] And the son of Atreus was seized with fear, and shouted to Antilochus: "Antilochus, thou art driving recklessly; nay, rein in thy horses! Here is the way straitened, but presently it will be wider for passing; lest haply thou work harm to us both by fouling my car."
But Antilochus guided his sure-footed horses off the track, charging up a little to one side. Atreus' son, alarmed, shouted at Antilochus: 'Antilochus, you're driving like an idiot! Pull your horses back! The road's too narrow. It gets wider soon—you can pass me there! Watch you don't hit me. You'll make us crash!'