Source : Webster's Revised Unabridged Dictionary (1913)

Petty \Pet"ty\, a. [Compar. {Pettier}; superl. {Pettiest}.] [OE.
   petit, F. petit; probably of Celtic origin, and akin to E.
   piece. Cf. {Petit}.]
   Little; trifling; inconsiderable; also, inferior;
   subordinate; as, a petty fault; a petty prince. --Denham.

         Like a petty god I walked about, admired of all.
                                                  --Milton.

   {Petty averages}. See under {Average}.

   {Petty cash}, money expended or received in small items or
      amounts.

   {Petty officer}, a subofficer in the navy, as a gunner, etc.,
      corresponding to a noncommissionned officer in the army.

   Note: For petty constable, petty jury, petty larceny, petty
         treason, See {Petit}.

   Syn: Little; diminutive; inconsiderable; inferior; trifling;
        trivial; unimportant; frivolous.

Source : WordNet®

petty
     adj 1: inferior in rank or status; "the junior faculty"; "a lowly
            corporal"; "petty officialdom"; "a subordinate
            functionary" [syn: {junior-grade}, {inferior}, {lower},
             {lower-ranking}, {lowly}, {petty(a)}, {secondary}, {subaltern},
             {subordinate}]
     2: (informal terms) small and of little importance; "a fiddling
        sum of money"; "a footling gesture"; "our worries are
        lilliputian compared with those of countries that are at
        war"; "a little (or small) matter"; "Mickey Mouse
        regulations"; "a dispute over niggling details"; "limited
        to petty enterprises"; "piffling efforts"; "giving a
        police officer a free meal may be against the law, but it
        seems to be a picayune infraction" [syn: {fiddling}, {footling},
         {lilliputian}, {little}, {Mickey Mouse}, {niggling}, {piddling},
         {piffling}, {picayune}, {trivial}]
     3: contemptibly narrow in outlook; "petty little comments";
        "disgusted with their small-minded pettiness" [syn: {small-minded}]
     [also: {pettiest}, {pettier}]