/mer"euh stem'/ , n. Bot.
embryonic tissue in plants; undifferentiated, growing, actively dividing cells.
[ 1870-75; merist ( ós ) divided, distributed (equiv. to * merid-, s. of merízein to divide into parts (deriv. of méris part, share) + -tos v. adj. suffix) + -em -ema termination of nouns denoting result of action; cf. -EME ]