'Meristem' definitions:

Definition of 'meristem'

From: WordNet
noun
Undifferentiated tissue from which new cells are formed, as at the tip of a stem or root

Definition of 'Meristem'

From: GCIDE
  • Meristem \Mer"i*stem\, n. [Gr. ? divisible.] (Bot.) A tissue of growing cells, or cells capable of further division. [1913 Webster]