hypocotyl
Botanical term for the part of a plant embryo below the cotyledons and above the radicle.
胚軸は、発芽後に子葉と根の間で伸びる部分です。
The hypocotyl is the part that elongates between the cotyledons and the root after germination.
embryonic axis
Zoological term for the main longitudinal axis of an embryo.
In animal embryonic development, the embryonic axis is involved in the formation of the anterior-posterior body axis.