The phrase "wast midair" refers to something that is completely pointless or wasteful. Synonyms for this phrase include "futile," "useless," "senseless," "fruitless," "unproductive," and "pointless." These words all convey the same idea of something that has no purpose or value. Other synonyms may include "vain," "ineffective," "unavailing," "empty," and "worthless." When trying to express the idea of something being wast midair, it's important to choose the right synonym, depending on the context and tone of the sentence. However, regardless of which synonym is chosen, they all communicate the same sense of futility and lack of purpose.