embryo
1 Americannoun
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embryos
plural
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the young of a viviparous animal, especially of a mammal, in the early stages of development within the womb, in humans up to the end of the second month.
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the rudimentary plant usually contained in the seed.
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any multicellular animal in a developmental stage preceding birth or hatching.
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the beginning or rudimentary stage of anything.
He charged that the party policy was socialism in embryo.
adjective
noun
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an animal in the early stages of development following cleavage of the zygote and ending at birth or hatching
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the human product of conception up to approximately the end of the second month of pregnancy Compare fetus
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a plant in the early stages of development: in higher plants, the plumule, cotyledons, and radicle within the seed
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an undeveloped or rudimentary state (esp in the phrase in embryo )
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something in an early stage of development
an embryo of an idea
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An animal in its earliest stage of development, before all the major body structures are represented. In humans, the embryonic stage lasts through the first eight weeks of pregnancy. In humans, other placental mammals, and other viviparous animals, young born as embryos cannot thrive. In marsupials, the young are born during the embryonic stage and complete their development outside the uterus, attached to a teat within the mother's pouch.
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The developing young of an egg-laying animal before hatching.
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The sporophyte of a plant in its earliest stages of development, such as the miniature, partially developed plant contained within a seed before germination.
Usage
What does embryo- mean? Embryo- is a combining form used like a prefix representing the word embryo. It is often used in scientific terms, especially in anatomy and biology. Embryo- ultimately comes from the Greek émbryos, meaning “ingrowing.”What are variants of embryo-?When combined with words or word elements that begin with a vowel, embryo- becomes embry-, as in embryectomy.
Discover More
The term is occasionally used to denote a new or developing idea or project: “The idea for the complete theory was already present in his work, in embryo form, in 1950.”
Other Word Forms
Derived Forms
Inflected Forms
Nouns
Etymology
Origin of embryo
First recorded in 1580–90; from Medieval Latin embryo, embryon-, from Greek émbryon, noun use of neuter of émbryos “ingrowing,” equivalent to em- “in” + bry- (stem of brýein “to swell”) + -os adjective suffix; em- 2
Explanation
An embryo is an animal in the phase after fertilization but before birth or hatching. Embryos still live in the womb or egg. Do you remember when you were an embryo? Probably not, because you were just a tiny clump of cells in your mother's womb — you weren't born yet. All animals were embryos at one point: it's a very early stage of life. Another meaning is not as literal: the beginning of an idea could be called an embryo, as in, "My plan for ice-skating robots is still in the embryo stage." That means the idea isn't very developed.
Vocabulary lists containing embryo
Animals (Zoology) - Introductory
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"Genes: All in the Family" and "How to See DNA"
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Plants (Botany) - Middle School
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
Quarterback Josh Allen is 30 years old—an embryo by Tommy Brady standards, but still.
From The Wall Street Journal ● Sep. 8, 2026
The embryo must successfully implant, and then even after implantation and a positive pregnancy test there’s risk of miscarriage.
From Slate ● Aug. 29, 2026
They discovered that the brain organoids continued to change and mature over the years, despite never having been inside an embryo, let alone a body.
From Barron's ● Aug. 19, 2026
"We are talking about people who did not simply draw lines, but organized them according to recurring principles -- parallelisms, grids, rotations and systematic repetitions: a visual grammar in embryo."
From Science Daily ● Aug. 9, 2026
It was hard to the touch and he knew that inside the embryo was solidly frozen.
From "Snow Falling on Cedars: A Novel" by David Guterson
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“The battle over embryos is becoming a big problem in divorces now.”
From MarketWatch ● Sep. 8, 2026
So unmarried couples with shared embryos may want to modify the terms of the contract signed with the fertility clinic as part of a prenup process.
From MarketWatch ● Sep. 8, 2026
As they grow, the yolk becomes smaller, and the embryos gain more room to shift position.
From Science Daily ● Sep. 1, 2026
The embryos do not remain locked into this right-handed arrangement throughout development.
From Science Daily ● Sep. 1, 2026
“He said: ‘Now, you embryos, here you are, all looking exactly the same, and We are going to give you the choice of what you want to be.
From "The Once and Future King" by T. H. White
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.