irreversible change
Technical term used in physics, chemistry, and other sciences to describe a process that cannot be reversed. Contrasts with 可逆変化 (reversible change).
See also: 可逆変化
In thermodynamics, irreversible change is treated as a process in which entropy increases.
この化学反応は不可逆変化であり、元の物質には戻らない。
This chemical reaction is an irreversible change and does not return to the original substances.