胚芽[haiga] germ (of a cereal, e.g. wheat, rice)
胚子[haishi] embryo
胚珠[haishu] ovule
胚胎[haitai] germination
胚乳[hainyuu] albumen (of a seed, esp. the endosperm)

胚葉[haiyou] germ (germinal, embryonic) layers
外胚葉[gaihaiyou] ectoderm
胚性幹細胞[haiseikansaibou] embryonic stem cell
胚性[haisei] embryonic