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amnion

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noun am·ni·on \ˈam-nē-ˌän, -ən\

Definition of amnion

plural amnions or am·niaplay \-nē-ə\

  1. 1 :  a thin membrane forming a closed sac about the embryos or fetuses of reptiles, birds, and mammals and containing the amniotic fluid

  2. 2 :  a membrane analogous to the amnion and occurring in various invertebrates

am·ni·ot·ic play \ˌam-nē-ˈä-tik\ adjective


Origin of amnion

New Latin, from Greek, caul, from amnos lamb — more at yean


First Known Use: 1667

Rhymes with amnion

Abadan, Acheron, Ahriman, aileron, alençon, amazon, Amazon, and so on, antiphon, Aragon, autobahn, balmacaan, Bantustan, baryon, Basilan, bear down on, beat up on, betatron, biathlon, cabochon, call upon, calutron, carillon, carry-on, carry on, celadon, check up on, chorion, colophon, come upon, Culiacán, cyclotron, decagon, decathlon, demijohn, dine out on, early on, echelon, electron, elevon, enteron, epsilon, ethephon, etymon, fall back on, fermion, follow-on, Genghis Khan, get it on, go back on, going on, goings-on, gonfalon, Grand Teton, graviton, hanger-on, harijan, helicon, heptagon, hereupon, hexagon, hold out on, hopping John, Huascarán, hyperon, Isfahan, isochron, Kublai Khan, Kyrgyzstan, lay eyes on, Lebanon, leprechaun, liaison, Lipizzan, load up on, logion, looker-on, macédoine, marathon, Marathon, marzipan, mastodon, Mazatlán, Miquelon, miss out on, morion, move in on, myrmidon, nonagon, noumenon, nucleon, Oberon, octagon, off and on, omicron, Oregon, organon, ostracon, Pakistan, Palawan, pantheon, paragon, Parmesan, parmigiana, Parthenon, peloton, pentagon, pentathlon, Percheron, Phlegethon, Phocion, pick up on, polygon, positron, Procyon, put-upon, Rajasthan, Ramadan, ride herd on, run low on, run out on, run upon, set eyes on, set foot on, set upon, silicon, sneak up on, Süleyman, tachyon, Taiyuan, talkathon, telamon, telethon, thereupon, tie one on, triathlon, Tucumán, upsilon, virion, walkathon, walk out on, whereupon, woebegone, work upon, Yerevan, Xiangtan, Zahedan


Medical Dictionary

amnion

play
noun am·ni·on \ˈam-nē-ˌän, -ən\

Medical Definition of amnion

plural amnions or am·nia \-nē-ə\play

  1. :  a thin membrane forming a closed sac about the embryos and fetuses of reptiles, birds, and mammals and containing the amniotic fluid—called also amniotic sac




Learn More about amnion

  1. Medical Dictionary: Definition of "amnion" Britannica.com: Encyclopedia article about "amnion"


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