The Collaborative International Dictionary of English v.0.48:

Estimative \Es"ti*ma*tive\, a. [Cf. F. estimatif.]
   1. Inclined, or able, to estimate; serving for, or capable of
      being used in, estimating.
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            We find in animals an estimative or judicial
            faculty.                              --Sir M. Hale.
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   2. Pertaining to an estimate. [R.]
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