embryo

1 of 2

noun

em·​bryo ˈem-brē-ˌō 

plural embryos

1

a

: an animal in the early stages of growth and differentiation that are characterized by cleavage, the laying down of fundamental tissues, and the formation of primitive organs and organ systems

especially : the developing human individual from the time of implantation to the end of the eighth week after conception

b

archaic : a vertebrate at any stage of development prior to birth or hatching

2

: the young sporophyte of a seed plant usually comprising a rudimentary plant with plumule, radicle, and cotyledons

3

a

: something as yet undeveloped

b

: a beginning or undeveloped state of something

productions seen in embryo during their out-of-town tryout period

—Henry Hewes

embryo-

2 of 2

combining form

: embryo

embryogeny

Examples of embryo in a Sentence

Recent Examples on the Web

Noun

Frozen embryo transfer: The provider freezes the embryos to be used later. —Khadeja Haye, Verywell Health, 26 Feb. 2025

In the fall of 2024, the couple decided to go the IVF route, successfully retrieving 24 eggs, but eventually was told only one embryo was viable. —Madeleine Marr, Miami Herald, 25 Feb. 2025

Early development was promising, and scientists transferred the embryo to Allie, Dolly’s surrogate mother. —Sarah Holzmann, Smithsonian Magazine, 22 Feb. 2025

Flashback: Alabama became the focal point for IVF and fertility care a year ago, when the state's Supreme Court ruled that frozen embryos created through IVF were children under state law. —Maya Goldman, Axios, 19 Feb. 2025

Word History

Etymology

Noun

Middle English embrioun "embryo, fetus," borrowed from Medieval Latin embrion-, embrio, embryo, borrowed from Greek émbryon "newborn creature (in reference to a lamb), young, embryo or fetus," from em- em- + -bryon, derivative of bry-, stem of brýein "to swell with an abundance of growth, bloom, abound," of obscure origin

Note: In Medieval Latin the Greek neuter noun émbryon was reanalyzed as the base of Latin nasal stems (such as sermōn-, sermō "speech"), resulting in the nominative singular form embryo, which was borrowed into English. The stem embryon- was employed in New Latin derivatives, the sources of embryonal and embryonic. Compare bryo-.

Combining form

Late Latin, from Greek, from embryon

First Known Use

Noun

1548, in the meaning defined at sense 1b

Phrases Containing embryo

• embryo sac
• embryo transfer
• in embryo

Rhymes for embryo

• acknow
• aglow
• ago
• airglow
• aloe
• altho
• although
• ammo
• backflow
• backhoe
• banjo
• barbeau

Kids Definition

embryo

noun

em·​bryo ˈem-brē-ˌō 

plural embryos

1

: an animal in the early stages of development that are marked by cleavage, the laying down of the basic tissues, and the formation of primitive organs and organ systems compare fetus

2

: a tiny young plant within a seed

3

: a beginning or undeveloped stage

—used especially in the phrase in embryo

Medical Definition

embryo

noun

em·​bryo ˈem-brē-ˌō 

plural embryos

1

archaic : a vertebrate at any stage of development prior to birth or hatching

2

: an animal in the early stages of growth and differentiation that are characterized by cleavage, the laying down of fundamental tissues, and the formation of primitive organs and organ systems

especially : the developing human individual from the time of implantation to the end of the eighth week after conception compare fetus