early 15c., divident, "that which serves as a barrier;"c. 1500, "act of dividing;" from Latin dividendum "thing to be divided," neuter gerundive of dividere "to force apart; to distribute" (see divide (v.)).
From late 15c. as "portion or share of anything to be divided." Sense of "sum to be divided into equal parts" is from 1620s, hence "portion of interest on a loan, stock, etc." Mathematical sense "number or quantity which is to be divided by another" is from 1540s (perhaps immediately from Middle French dividende "a number divided by another"). Related: Dividends.