imperforate

from WordNet (r) 3.0 (2006)

imperforate
    adj 1: not perforated; having no opening

from The Collaborative International Dictionary of English v.0.48

Imperforate \Im*per"fo*rate\, Imperforated \Im*per"fo*ra"ted\,
   a. [L. pref. im- not + perforatus, p. p. of perforate to
   perforate. See {Perforate}.]
   Not perforated; having no opening or aperture. --Sir J.
   Banks.
   [1913 Webster]