Overhead works as both an adjective and an adverb: "An overhead view of the football field gives the spectators a better idea of the game, and a drone flying overhead is the perfect way to achieve it." There's also an overhead stroke in tennis, an overhead projector showing a movie in science class, and the overhead, ...

What type of word is overhead?

overhead adjective, adverb [not gradable] (IN AIR)

Is overhead an adjective?

OVERHEAD (adjective, adverb) definition and synonyms | Macmillan Dictionary.