Ir`re·mis'si·ble adjective [ Latin irremissibilis : confer French irrémissible . See In- not, and Remissible .] Not remissible; unpardonable; as, irremissible crimes. Burke. -- Ir`re*mis'si*ble , noun -- Ir`re*mis'si... Found on http://www.encyclo.co.uk/webster/I/98