It is a sentence. "Wait up" means wait for me.
Wait a tick, hold on a tick, is asking you to wait a moment. A tick refers to the ticking of a clock.
I can't see why you wait for her. If you wait for the train, it'll stop at this platform.
The verb in the sentence is "wait."
The clerk will wait on whom is next is the proper sentence. Who is only used when it is the subject of a verb.
the jubilant dog couldn't wait to get his steak
He wanted a prosecution quickly, but he had to wait for due process of law first.
Went.
i need to Wait
The imperative command ("Wait!") is a sentence. It is equivalent to "you should wait" or "you must wait". The subject (you) is understood, as in other forms of direct address.
We will have to wait for the rigger to set up the scaffolding before we can start the work.
In this sentence, "until" is used to specify a timeframe. Janice will continue waiting for us until noon, after which she will leave. It indicates the limit of time for her to wait before departing.
Im coming, Wait!