diductio

dīductĭo, ōnis, f. [diduco],

an expanding, separating (very rare; perh. only in Seneca): ostendit intentionem spiritus velocitas ejus et diductio, Sen. Q. N. 2, 8, 2: in diductione rerum, in dividing, separating the elements , id. ib. 3, 13, 2.