Overhead and Sustentation

Overhead noun - (nautical) the top surface of an enclosed space on a ship.

Sustentation and overhead are semantically related In some cases you can use "Sustentation" instead a noun "Overhead".

Sustentation noun - The act or activity of keeping something in an existing and usually satisfactory condition.

Overhead and sustentation are semantically related in maintenance topic. Sometimes you can use "Overhead" instead a noun "Sustentation".