Where does “hæmoblast” come from?

hæmoblast (English) comes from English -blast, from Ancient Greek βλᾰστός — sprout, shoot, bud.

Ancestry of “hæmoblast”, step by step

Step	Language	Word	Meaning
1	English	-blast	an immature cell or tissue
2	Ancient Greek	βλᾰστός	sprout, shoot, bud