n.
Pronunciation: ' äp-t ə -m ə m
Function: noun
Inflected Form: plural -ma \ -m ə \ also -mums
Etymology: L
Date: 1879
1 : the amount or degree of something that is most favorable to some end especially : the most favorable condition for the growth and reproduction of an organism
2 : greatest degree attained or attainable under implied or specified conditions
– optimum adjective