osculum

[os-kyuh-luh m] /ˈɒs kyə ləm/
noun, plural oscula
[os-kyuh-luh] /ˈɒs kyə lə/ (Show IPA)
1.
a small mouthlike aperture, as of a sponge.
Origin
1605-15; < Neo-Latin, Latin ōsculum, equivalent to ōs mouth + -culum -cule1
British Dictionary definitions for osculum

osculum

/ˈɒskjʊləm/
noun (pl) -la (-lə)
1.
(zoology) a mouthlike aperture, esp the opening in a sponge out of which water passes
Word Origin
C17: from Latin: a kiss, little mouth, diminutive of ōs mouth
osculum in Medicine

osculum os·cu·lum (ŏs'kyə-ləm)
n. pl. os·cu·la (-lə)
A pore or minute opening.