I. (ˈ)im, əm+ adjective
Etymology: in- (I) + perforate
1. : not perforated : having no opening or aperture ; specifically : lacking the normal opening
an imperforate anus
2. of a stamp or a sheet of stamps : lacking perforations or rouletting
3. : having the umbilicus obliterated by the later whorls — used of various spiral shells
II. noun
( -s )
: an imperforate stamp