The Collaborative International Dictionary of English v.0.48:

Lucrative \Lu"cra*tive\, a. [L. lucrativus, fr. lucrari to gain,
   fr. lucrum gain: cf. F. lucratif. See Lucre.]
   [1913 Webster]
   1. Yielding lucre; gainful; profitable; making increase of
      money or goods; as, a lucrative business or office.
      [1913 Webster]

            The trade of merchandise being the most lucrative,
            may bear usury at a good rate.        --Bacon.
      [1913 Webster]

   2. Greedy of gain. [Obs.]
      [1913 Webster]

            Such diligence as the most part of our lucrative
            lawyers do use, in deferring and prolonging of
            matters and actions from term to term. --Latimer.
      [1913 Webster]

WordNet (r) 3.0 (2006):

lucrative
    adj 1: producing a sizeable profit; "a remunerative business"
           [syn: lucrative, moneymaking, remunerative]

Moby Thesaurus II by Grady Ward, 1.0:

23 Moby Thesaurus words for "lucrative":
   advantageous, banausic, breadwinning, compensating, compensative,
   compensatory, fat, gainful, good, moneymaking, paying, productive,
   profitable, remunerative, reparative, repaying, retributive,
   retributory, rewardful, rewarding, satisfying, well-paying,
   worthwhile