Salt wife

A Salt wife is a concubine in Ironborn culture. They are usually the women kidnapped during raids. An ironborn may keep several salt wives, but only one "rock wife", which is of ironborn origin.

Salt wives have a low status in ironborn society.

Example
The Captain's daughter aboard the Myraham offers to become Theon Greyjoys's salt wife after she takes her as his lover during his voyage to Pyke.