A [http://www.EFNMS.org European Federation of National Maintenance Societies] defines maintenance when:

Everthing actions which stand as an objective to locate an item within or even restore it to, a state where it might perform the expected work. A actions include a combination of everthing technical indicator & corresponding administrative, managerial, & oversight actions.

Inside telecommunication, the term maintenance has a below meanings:

I. Any activity, like tests, measuring, replacements, adjustments & repairs, meant to restore or even locate the functional unit in a specified state where a unit might perform its called upon functions.

Deuce. [For material], Tons action taken to locate poop inside the serviceable problem or even to restore it to usability. It includes review, touching, service, classification when to usableness, repair, rebuilding, and reclamation.

Tierce. [For material], Completely supply & repair action taken to keep the click conditioned to carry out its mission.

Quartet. [For material], the routine recurring function expected to keep a facility (plant, building, structure, ground facility, utility system, or even more real property) inside such problem that it can be day & night utilized, at its original or intentional capacity and efficiency for its intended purpose.

Source: from either Federal Standard 1037C and from MIL-STD-188 and from a Department of Defense Dictionary of Military and Associated Terms