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definitions

imperforate

[im-pur-fer-it, -fuh-reyt]
adjective
  1. Also im·per·fo·rat·ed. not perforate; having no perforation.
  2. Philately. (of a number of stamps joined together) lacking the perforations usually separating individual stamps.
noun
  1. an imperforate stamp.

Origin of imperforate

First recorded in 1665–75; im-2 + perforate
Related formsim·per·fo·ra·tion, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for imperforation

imperforate

adjective
  1. not perforated
  2. (of a postage stamp) not provided with perforation or any other means of separationAbbreviation: imperf Compare perforate
  3. anatomy (of a bodily part, such as the anus) without the normal opening
Derived Formsimperforation, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for imperforation

imperforate

adj.

1670s, from im- + perforate (adj.).

Online Etymology Dictionary, © 2010 Douglas Harper
imperforation in Medicine

imperforation

[ĭm-pûr′fə-rā′shən]
n.
  1. The condition of being abnormally occluded or closed.

imperforate

[ĭm-pûr′fər-ĭt]
adj.
  1. Lacking a normal opening.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.