amnion

[ am-nee-uhn ]
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noun,plural am·ni·ons, am·ni·a [am-nee-uh]. /ˈæm ni ə/.
  1. Anatomy, Zoology. the innermost of the embryonic or fetal membranes of reptiles, birds, and mammals; the sac in which the embryo is suspended.

  2. Zoology. a similar membrane of insects and other invertebrates.

Origin of amnion

1
1660–70; <Greek, equivalent to amn(ós) lamb (see yean) + -ion diminutive suffix

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British Dictionary definitions for amnion

amnion

/ (ˈæmnɪən) /


nounplural -nions or -nia (-nɪə)
  1. the innermost of two membranes enclosing an embryonic reptile, bird, or mammal: See also chorion

Origin of amnion

1
C17: via New Latin from Greek: a little lamb, from amnos a lamb

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

Scientific definitions for amnion

amnion

[ ămnē-ən ]


  1. A thin, membranous sac filled with a watery fluid (called the amniotic fluid) in which the embryo or fetus of a reptile, bird, or mammal is suspended during prenatal development. Also called amniotic sac

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