A wait is the time it takes for something to happen. The wait to get the brand new computer was four hours long, but it was worth it.
The word wait originated in the 1200s, from the Old Northern French word waitier: "to watch with hostile intent." Even back then, people didn't like to wait. Anticipating something that will happen is waiting, though sometimes what you wait for never comes — like Godot, who never shows up in the play "Waiting for Godot." When you wait to do something, you delay. When you wait tables, you serve people, preferably without delay.