Definition: [adverb] above the level of the head; in the sky.
Example: a helicopter buzzed overhead
Definition: [adjective] situated above the level of the head.
Example: the sun was directly overhead
Definition: [adjective] (of a driving mechanism) above the object driven.
Example: an overhead cam four-cylinder engine
Definition: [adjective] (of a cost or expense) incurred in the upkeep or running of a plant, premises, or business and not attributable to individual products or items.
Example: government departments generally baulk at paying full overhead costs
Definition: [noun] an overhead cost or expense.
Example: overheads, such as lighting, equipment, and any little extras, are paid for out of a centralized fund
Definition: [noun] a transparency designed for use with an overhead projector.
Example: software for producing slides, charts, and overheads
Definition: [noun] an overhead compartment, especially on an aircraft.
Example: passengers get up to fiddle with their luggage in the overheads