The Collaborative International Dictionary of English v.0.48:

Cunabula \Cu*nab"u*la\ (k[-u]*n[a^]b"[-u]*l[.a]), n. pl. [L., a
   cradle, earliest abode, fr. cunae cradle.]
   1. The earliest abode; original dwelling place; originals;
      as, the cunabula of the human race.
      [1913 Webster]

   2. (Bibliography) The extant copies of the first or earliest
      printed books, or of such as were printed in the 15th
      century.
      [1913 Webster]