NOUN (3)

1. a line of small holes for tearing at a particular place;

2. a hole made in something;
- Example: "a perforation of the eardrum"

3. the act of punching a hole (especially a row of holes as for ease of separation);

The Collaborative International Dictionary of English v.0.48:

Perforation \Per`fo*ra"tion\, n. [Cf. F. perforation.]
   1. The act of perforating, or of boring or piercing through.
      --Bacon.
      [1913 Webster]

   2. A hole made by boring or piercing; an aperture. "Slender
      perforations." --Sir T. Browne.
      [1913 Webster]

WordNet (r) 3.0 (2006):

perforation
    n 1: a line of small holes for tearing at a particular place
    2: a hole made in something; "a perforation of the eardrum"
    3: the act of punching a hole (especially a row of holes as for
       ease of separation)

Moby Thesaurus II by Grady Ward, 1.0:

24 Moby Thesaurus words for "perforation":
   acupunctuation, acupuncture, bore, boring, broach, drill hole,
   empiercement, fixing, goring, impalement, lancing, penetration,
   piercing, pricking, punching, puncture, puncturing, skewering,
   terebration, transfixation, transfixion, transforation, trepanning,
   trephining