The Collaborative International Dictionary of English v.0.48:

Adapid \Adapid\ n.
   1. 1 extinct small mostly diurnal lower primates that fed on
      leaves and fruit; abundant in North America and Europe 30
      to 50 million years ago; their descendents probably
      include the lemurs and lorises; some authorities consider
      them ancestral to anthropoids but others consider them
      only cousins.

   Syn: Adapid group
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Adapid
    n 1: extinct small mostly diurnal lower primates that fed on
         leaves and fruit; abundant in North America and Europe 30
         to 50 million years ago; their descendents probably include
         the lemurs; some authorities consider them ancestral to
         anthropoids but others consider them only cousins [syn:
         Adapid, Adapid group]