A doodad is a kind of object in Warcraft III, as opposed to regions, units, cameras, and terrain. Doodads also appear in World of Warcraft such as trees, bushes, buildings, walls, etc.
Usually one cannot interact with a doodad, the exception being destructables (i.e. trees). Similar to terrain, doodads are used to create parts of an environment that cannot be shown by ground coloring/elevation/water, for example, a fireplace in a Creep Camp.