janitor(n = noun.person) - someone employed to clean and maintain a building;
is a kind of custodian, keeper, steward

1.  A door-keeper; a porter. [1913 Webster]

2.  One who is employed to care for a public building, or a building occupied for offices, suites of rooms, etc.; a caretaker; -- the duties may include removal of trash, cleaning of the rooms and public areas, and minor repairs. [1913 Webster]

janitor, n.
1 a doorkeeper.
2 a caretaker of a building.

Derivative:
janitorial adj.

Etymology:
L f. janua door

N  stopper, stopple, plug, cork, bung, spike, spill, stopcock, tap, rammer, ram, ramrod, piston, stop-gap, wadding, stuffing, padding, stopping, dossil, pledget, tompion, tourniquet, cover, valve, vent peg, spigot, slide valve, janitor, doorkeeper, porter, warder, beadle, cerberus, ostiary.