[ gas-troo-luh ]
/ ˈgæs trʊ lə /
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noun, plural gas·tru·las, gas·tru·lae [gas-troo-lee]. /ˈgæs trʊˌli/. Embryology.
a metazoan embryo in an early state of germ layer formation following the blastula stage, consisting of a cuplike body of two layers of cells, the ectoderm and endoderm, enclosing a central cavity, or archenteron, that opens to the outside by the blastopore: in most animals progressing to the formation of a third cell layer, the mesoderm.


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Origin of gastrula

From New Latin, dating back to 1875–80; see origin at gastro-, -ule


gas·tru·lar, adjectivepre·gas·tru·lar, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use gastrula in a sentence

British Dictionary definitions for gastrula

/ (ˈɡæstrʊlə) /

noun plural -las or -lae (-ˌliː)
a saclike animal embryo consisting of three layers of cells (ectoderm, mesoderm, and endoderm) surrounding a central cavity (archenteron) with a small opening (blastopore) to the exteriorSee also ectoderm, mesoderm, endoderm

Derived forms of gastrula

gastrular, adjective

Word Origin for gastrula

C19: New Latin: little stomach, from Greek gastēr belly
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

Medical definitions for gastrula

[ găstrə-lə ]

n. pl. gas•tru•las
An embryo at the stage following the blastula, consisting of a hollow, two-layered sac of ectoderm and endoderm surrounding an archenteron that communicates with the exterior through the blastopore.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for gastrula

[ găstrə-lə ]

Plural gastrulas gastrulae (găstrə-lē′)
An animal embryo at the stage following the blastula. The gastrula develops from the blastula by invagination (inpocketing), forming an inner cavity with an opening and causing the cells to be distributed into an outer layer (ectoderm) and an inner layer (endoderm). In complex animals such as vertebrates, a third layer (mesoderm) also forms. These layers later develop into the organs and tissues of the body. In vertebrates and other deuterostomes, the opening of the gastrula becomes the anus, while in protostomes (such as arthropods), it becomes the mouth.♦ The development of an embryo from blastula to gastrula is called gastrulation. Compare blastula.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.