The action or an act of paying off a debt, liability, etc., gradually by making regular repayments over a period of time.
Cent. Dict. (1889) records admortization as a variant of amortization but does not specify whether it was attested in both the modern and the historical sense.
Mid 18th century (in an earlier sense). Variant or alteration of amortization, probably originally after either post-classical Latin admortization-, admortizatio, variant of amortizatio amortization, or Middle French admortisation, admortization.