There are several synonyms for the phrase "wast mid-air" which can be used to describe something that has suddenly disappeared or vanished without a trace. Some examples include "vanished into thin air," "disappeared into the ether," "evaporated into nothingness," and "gone in a puff of smoke." These phrases emphasize the suddenness and mysteriousness of the disappearance, suggesting that something has been lost or taken away without explanation. Whether used in a literal or figurative sense, these synonyms help to convey the sense of sudden loss or absence that comes with something disappearing without a trace.