/sep"teuhm/ , n. , pl. septa /-teuh/ . Biol.
a dividing wall, membrane, or the like, in a plant or animal structure; dissepiment.
[ 1710-20; septum, var. of saeptum enclosure, n. use of neut. of saeptus (ptp. of saepire to fence); akin to saepes hedge, fence ]