The Collaborative International Dictionary of English v.0.48:

Commodore \Com"mo*dore`\, n. [Prob. a corruption of commander,
   or Sp. comendador a knight of a military order who holds a
   commandery; also a superior of a monastery, fr. LL.
   commendare to command. Cf. Commend, Command,
   Commander.]
   1. (U. S. Navy) An officer who ranks next above a captain;
      sometimes, by courtesy, the senior captain of a squadron.
      The rank of commodore corresponds with that of brigadier
      general in the army.
      [1913 Webster]

   2. (British Navy) A captain commanding a squadron, or a
      division of a fleet, or having the temporary rank of rear
      admiral.
      [1913 Webster]

   3. A title given by courtesy to the senior captain of a line
      of merchant vessels, and also to the chief officer of a
      yachting or rowing club.
      [1913 Webster]

   4. A familiar for the flagship, or for the principal vessel
      of a squadron or fleet.
      [1913 Webster]

WordNet (r) 3.0 (2006):

commodore
    n 1: a commissioned naval officer who ranks above a captain and
         below a rear admiral; the lowest grade of admiral

The Free On-line Dictionary of Computing (30 December 2018):

Commodore

    Commodore Business Machines or one of
   their computers such as the Commodore 64.

   (2010-09-14)


U.S. Gazetteer Places (2000):

Commodore, PA -- U.S. Census Designated Place in Pennsylvania
   Population (2000):    337
   Housing Units (2000): 147
   Land area (2000):     0.768239 sq. miles (1.989730 sq. km)
   Water area (2000):    0.003810 sq. miles (0.009867 sq. km)
   Total area (2000):    0.772049 sq. miles (1.999597 sq. km)
   FIPS code:            15464
   Located within:       Pennsylvania (PA), FIPS 42
   Location:             40.710694 N, 78.945857 W
   ZIP Codes (1990):     15729
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Commodore, PA
    Commodore