The Collaborative International Dictionary of English v.0.48:

Increscent \In*cres"cent\, a. [L. increscens, -entis, p. pr. of
   increscere. See Increase.]
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   1. Increasing; growing; augmenting; swelling; enlarging.
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            Between the incresent and decrescent moon.
                                                  --Tennyson.
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   2. (Her.) Increasing; on the increase; -- said of the moon
      represented as the new moon, with the points turned toward
      the dexter side.
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