n. (pl. -os) 1 a an unborn or unhatched offspring. b a human offspring in the first eight weeks from conception. 2 a rudimentary plant contained in a seed. 3 a thing in a rudimentary stage. 4 (attrib.) undeveloped, immature. in embryo undeveloped. embryoid adj. embryonal adj. embryonic adj. embryonically adv.
[ LL embryo -onis f. Gk embruon foetus (as EN-(2), bruo swell, grow) ]