inexpiable

adjective

Impossible to expiate or atone for.

adjective

Implacable.

Not to be expiated; admitting of no expiation or atonement: as, an inexpiable crime or offense.

Not to be satisfied or appeased by expiation; implacable.

adjective

Admitting of no expiation, atonement, or satisfaction.

adjective

Incapable of being mollified or appeased; relentless; implacable.

adjective

both unforgivable and inexplicable

adjective

incapable of being atoned for