The Collaborative International Dictionary of English v.0.48:

Pyroelectric \Pyr`o*e*lec"tric\, a. [Pyro- + electric.]
   (Physics)
   Pertaining to, or dependent on, pyroelectricity; receiving
   electric polarity when heated.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Pyroelectric \Pyr`o*e*lec"tric\, n. (Physics)
   A substance which becomes electrically polar when heated,
   exhibiting opposite charges of statical electricity at two
   separate parts, especially the two extremities.
   [1913 Webster]

WordNet (r) 3.0 (2006):

pyroelectric
    adj 1: relating to or exhibiting pyroelectricity [syn:
           pyroelectric, pyroelectrical]