read-only memory (ROM)

A memory in which the contents are intended to be read only and not to be altered during normal operation. (Ref. IEC 748‑2.)

NOTE Unless otherwise qualified, the term "read-only memory" implies that the data content is determined by the structure of the memory and is unalterable.

References: 

JESD21-C#, 1/97
JESD100-B, 12/99