The Collaborative International Dictionary of English v.0.48:

Thrift \Thrift\ (thr[i^]ft), n. [Icel. [thorn]rift. See
   Thrive.]
   1. A thriving state; good husbandry; economical management in
      regard to property; frugality.
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            The rest, . . . willing to fall to thrift, prove
            very good husbands.                   --Spenser.
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   2. Success and advance in the acquisition of property;
      increase of worldly goods; gain; prosperity. "Your thrift
      is gone full clean." --Chaucer.
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            I have a mind presages me such thrift. --Shak.
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   3. Vigorous growth, as of a plant.
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   4. (Bot.) One of several species of flowering plants of the
      genera Statice and Armeria.
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   Common thrift (Bot.), Armeria vulgaris; -- also called
      sea pink.
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   Syn: Frugality; economy; prosperity; gain; profit.
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WordNet (r) 3.0 (2006):

thrift
    n 1: any of numerous sun-loving low-growing evergreens of the
         genus Armeria having round heads of pink or white flowers
    2: extreme care in spending money; reluctance to spend money
       unnecessarily [syn: parsimony, parsimoniousness,
       thrift, penny-pinching]