(1):

(n.) The act of obtaining by separation, or as the result of eliminating; deduction. [See Eliminate, 4.]

(2):

(n.) The act of expelling or throwing off

(3):

(n.) the act of discharging or excreting waste products or foreign substances through the various emunctories.

(4):

(n.) Act of causing a quantity to disappear from an equation; especially, in the operation of deducing from several equations containing several unknown quantities a less number of equations containing a less number of unknown quantities.