'augend' originates from Latin, specifically the verb 'augēre' (to increase) combined with the gerundive/participial element '-endus' meaning 'to be (done)', forming a sense of 'that which is to be increased'.

'augend' developed from the Latin gerundive form 'augendus' and entered English usage in mathematical contexts in the early modern period (around the 17th century) to denote the quantity to be increased; it was adopted into English technical vocabulary without major phonological change.

Initially it meant 'that which is to be increased' in a general sense; over time it took the narrower technical meaning 'the number to which another number is added' in arithmetic.