orderly
adv.
late 15c., "in due order," from order + -ly(2).
adj.
"arranged in order," 1570s, from order, n. + -ly(1).
n.
"military attendant who carries orders," 1781, short for orderly corporal, etc. Extended 1809 to an attendant at a hospital (originally a military hospital) charged with keeping things in order and clean. See orderly, adj..