An apical meristem; specifically the region of a meristem comprising cells that have not yet undergone any of the changes associated with tissue differentiation.
Origin
Late 19th century. After German Urmeristem.
Definition of promeristem in US English:
promeristem
noun
Botany
An apical meristem; specifically the region of a meristem comprising cells that have not yet undergone any of the changes associated with tissue differentiation.