In zoological nomenclature, a nomen oblitum (plural: nomina oblita; Latin for 'forgotten name') is a scientific name that has been declared to be obsolete (figuratively "forgotten") in favor of a "protected" name.

The designation nomen oblitum with its present meaning commenced with the fourth edition (1999) of the International Code of Zoological Nomenclature. After 1 January 2000, a scientific name may be