aestivate

from WordNet (r) 3.0 (2006)

aestivate
    v 1: sleep during summer; "certain animals estivate" [syn:
         {estivate}, {aestivate}] [ant: {hibernate}, {hole up}]

from The Collaborative International Dictionary of English v.0.48

AEstivate \[AE]s"ti*vate\, v. i. [L. aestivare, aestivatum.]
   1. To spend the summer.
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   2. (Zool.) To pass the summer in a state of torpor.
      [1913 Webster] [Spelt also {estivate}.]
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