The Collaborative International Dictionary of English v.0.48:
Overhead \O`ver*head"\, adv.
Aloft; above; in or attached to the ceiling or roof; in the
story or upon the floor above; in the zenith.
While overhead the moon
Sits arbitress. --Milton.
Note: Also used adjectively; as, an overhead crane, gear,
Overhead engine, a vertical steam engine in which the
cylinder stands above the crank.
Overhead work, a general term in manufactories for
countershafting and gearing, when overhead.