1. (noun)embryo (botany) a minute rudimentary plant contained within a seed or an archegonium Synonyms: fertilized egg, conceptus
2. (noun)embryo, conceptus, fertilized egg an animal organism in the early stages of growth and differentiation that in higher forms merge into fetal stages but in lower forms terminate in commencement of larval life Synonyms: fertilized egg, embryo, conceptus