n., pl., -os.
- An organism in its early stages of development, especially before it has reached a distinctively recognizable form.
- An organism at any time before full development, birth, or hatching.
- The fertilized egg of a vertebrate animal following cleavage.
- In humans, the prefetal product of conception from implantation through the eighth week of development.
- Botany. The minute, rudimentary plant contained within a seed or an archegonium.
- A rudimentary or beginning stage: "To its founding fathers, the European [Economic] Community was the embryo of the United States of Europe" (Economist).
[Medieval Latin embryō, from Greek embruon : en-, in; see en-2 + bruein, to be full to bursting.]
The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.