The Collaborative International Dictionary of English v.0.48:

Orderly \Or"der*ly\, n.; pl. Orderlies.
   1. (Mil.) A noncommissioned officer or soldier who attends a
      superior officer to carry his orders, or to render other
      service.
      [1913 Webster]

            Orderlies were appointed to watch the palace.
                                                  --Macaulay.
      [1913 Webster]

   2. A street sweeper. [Eng.] --Mayhew.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Orderly \Or"der*ly\, a.
   1. Conformed to order; in order; regular; as, an orderly
      course or plan. --Milton.
      [1913 Webster]

   2. Observant of order, authority, or rule; hence, obedient;
      quiet; peaceable; not unruly; as, orderly children; an
      orderly community.
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   3. Performed in good or established order; well-regulated.
      "An orderly . . . march." --Clarendon.
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   4. Being on duty; keeping order; conveying orders.
      "Aids-de-camp and orderly men." --Sir W. Scott.
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   Orderly book (Mil.), a book for every company, in which the
      general and regimental orders are recorded.

   Orderly officer, the officer of the day, or that officer of
      a corps or regiment whose turn it is to supervise for the
      day the arrangements for food, cleanliness, etc. --Farrow.

   Orderly room.
      (a) The court of the commanding officer, where charges
          against the men of the regiment are tried.
      (b) The office of the commanding officer, usually in the
          barracks, whence orders emanate. --Farrow.

   Orderly sergeant, the first sergeant of a company.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Orderly \Or"der*ly\, adv.
   According to due order; regularly; methodically; duly.
   [1913 Webster]

         You are blunt; go to it orderly.         --Shak.
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WordNet (r) 3.0 (2006):

orderly
    adj 1: devoid of violence or disruption; "an orderly crowd
           confronted the president" [ant: disorderly]
    2: clean or organized; "her neat dress"; "a neat room" [syn:
       neat, orderly]
    n 1: a soldier who serves as an attendant to a superior officer;
         "the orderly laid out the general's uniform"
    2: a male hospital attendant who has general duties that do not
       involve the medical treatment of patients [syn: orderly,
       hospital attendant]

Moby Thesaurus II by Grady Ward, 1.0:

213 Moby Thesaurus words for "orderly":
   Ganymede, Hebe, X-ray technician, accordant, accurate, adjutant,
   airline hostess, airline stewardess, aligned, alike, always,
   anesthetist, arranged, arrayed, assistant, assorted, at every turn,
   at peace, attendant, automatic, balanced, batman, bellboy, bellhop,
   bellman, bloodless, bootblack, boots, businesslike, cabin boy,
   caddie, calm, categorized, chipper, chore boy, civil, civilized,
   classified, composed, concinnate, concinnous, concordant,
   connected, consecutive, consistent, consonant, constant,
   constantly, constituted, continually, continuous, conventional,
   copyboy, correct, correspondent, courteous, cupbearer, decorous,
   dietitian, disciplined, disorderly, disposed, dresser, equable,
   equal, errand boy, errand girl, euphonic, euphonical, euphonious,
   even, exact, fixed, flat, flowing, fluent, footboy, formal,
   general, gofer, graded, grouped, habitual, halcyon, harmonious,
   harmonized, homogeneous, hospital administrator, hostess, idyllic,
   immutable, in apple-pie order, in hand, invariable, invariably,
   joined, laboratory technician, law-abiding, level, like clockwork,
   mannerly, marshaled, measured, mechanical, menial, messenger,
   methodic, methodical, methodically, methodized, meticulous,
   monolithic, natural, naturalistic, naturistic, neat,
   never otherwise, normal, normalized, of a piece, office boy,
   office girl, ordered, organized, pacific, page, pastoral,
   peaceable, peaceful, peacetime, persistent, physical therapist,
   physiotherapist, piping, placed, polite, precious, precise,
   precisian, precisionist, punctilious, puristic, quiet,
   radiographer, radiotherapist, ranged, ranked, realistic, regular,
   regular as clockwork, regularized, regularly, regulated, restful,
   robotlike, routine, routinized, scrupulous, sequent, sequential,
   serene, serial, servant, shipshape, smooth, smooth-sounding, snug,
   soft, sorted, squire, stable, standardized, steadfast, steadily,
   steady, steward, stewardess, sweet, symmetrical, synchronized,
   systematic, systematically, systematized, systemized, tender, tidy,
   tight, trainbearer, tranquil, tripping, typical, unbroken,
   unchangeable, unchanged, unchanging, undeviating, undifferentiated,
   undiversified, unexceptional, uniform, uninterrupted, unruffled,
   untroubled, unvaried, unvarying, usher, usual, well-behaved,
   well-mannered, well-ordered, well-regulated, without exception,
   yeoman