The Collaborative International Dictionary of English v.0.48:

Grouper \Group"er\, n. [Corrupted fr. Pg. garupa crupper. Cf.
   Garbupa.] (Zool.)
   (a) One of several species of valuable food fishes of the
       genus Epinephelus, of the family Serranid[ae], as the
       red grouper, or brown snapper (Epinephelus morio), and
       the black grouper, or warsaw (Epinephelus nigritus),
       both from Florida and the Gulf of Mexico.
   (b) The tripletail (Lobotes).
   (c) In California, the name is often applied to the
       rockfishes. [Written also groper, gruper, and
       trooper.]
       [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Trooper \Troop"er\, n.
   1. A soldier in a body of cavalry; a cavalryman; also, the
      horse of a cavalryman.
      [1913 Webster]

   2. A state police officer; -- also called state trooper.
      [U. S.]
      [PJC]

   3. A mounted policeman. [Australia]

   Note: The black troopers of Queensland are a regiment of
         aboriginal police, employed chiefly for dispersing wild
         aborigines who encroach on sheep runs.
         [Webster 1913 Suppl.]

   4. Trouper.
      [PJC]

   like a trooper, with energy, endurance, or enthusiasm; as,
      to work like a trooper.

WordNet (r) 3.0 (2006):

trooper
    n 1: a soldier in a motorized army unit [syn: cavalryman,
         trooper]
    2: a mounted policeman
    3: a state police officer [syn: trooper, state trooper]
    4: a soldier mounted on horseback; "a cavalryman always takes
       good care of his mount" [syn: cavalryman, trooper]

Moby Thesaurus II by Grady Ward, 1.0:

91 Moby Thesaurus words for "trooper":
   Cheka, FBI, G-man, Gestapo, Interpol, MP, MVD, Mounties, NKVD,
   OGPU, RCMP, SP, Scotland Yard, bailiff, beadle, beagle,
   bound bailiff, captain, catchpole, cavalryman, charger,
   chief of police, commissioner, constable, constabulary, cossack,
   county police, courser, cuirassier, deputy, deputy sheriff,
   detective, dragoon, fed, federal, flic, gendarme, government man,
   heavy dragoon, highway patrol, hussar, inspector, lance, lancer,
   law enforcement agency, lictor, lieutenant, mace-bearer, marshal,
   military police, mounted policeman, narc, officer, patrolman,
   peace officer, police, police captain, police commissioner,
   police constable, police force, police inspector, police matron,
   police officer, police sergeant, policeman, policewoman,
   political police, portreeve, posse, provincial police, reeve,
   riot police, roundsman, secret police, security force, sergeant,
   sergeant at arms, sheriff, shore patrol, spahi, special police,
   state police, superintendent, tactical police, tipstaff, tipstaves,
   troopers, uhlan, vigilance committee, vigilantes, war-horse



U.S. Gazetteer Places (2000):

Trooper, PA -- U.S. Census Designated Place in Pennsylvania
   Population (2000):    6061
   Housing Units (2000): 2107
   Land area (2000):     2.379740 sq. miles (6.163497 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    2.379740 sq. miles (6.163497 sq. km)
   FIPS code:            77520
   Located within:       Pennsylvania (PA), FIPS 42
   Location:             40.148845 N, 75.397170 W
   ZIP Codes (1990):
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Trooper, PA
    Trooper