"wait time" and "waiting time" are the same. However, "wait time" is much more common. What is the wait time for this amusement park ride? "wait times" is just the plural of "wait time". The wait times today are too long! (for all the rides at the park, for example) "a wait time" refers to a specific wait time. A: What is the wait time for this ride? B: The wait time is 1 hour. or B: There is a wait time of 1 hour.

Se my response to your earlier question. IN certain contexts, these are all acceptable. However, standing by themselves, aside from possibly "a wait time", these have no meaning other than what the words mean at face value.

Waiting time ?