The Collaborative International Dictionary of English v.0.48:

Insectivorous \In`sec*tiv"o*rous\, a. [See Insectivora.]
   Feeding or subsisting on insects; carnivorous. The term is
   applied:
   (a) to plants which have some special adaptation for catching
       and digesting insects, as the sundew, Venus's flytrap,
       Sarracenia, etc.
   (b) to the Insectivora, and many bats, birds, and reptiles.
       [1913 Webster]

WordNet (r) 3.0 (2006):

insectivorous
    adj 1: (of animals and plants) feeding on insects [ant:
           carnivorous, herbivorous, omnivorous]