nonvolatile
adjective
non·vol·a·tile ˌnän-ˈvä-lə-tᵊl 
: not volatile: such as
a
: not vaporizing readily
a nonvolatile solvent
b
of a computer memory : retaining data when power is shut off
Example Sentences
Recent Examples on the Web As the moniker implies, these assets are supposed to be the nonvolatile cousins of bitcoin, dogecoin and other digital assets that are prone to sharp swings. 
Caitlin Ostroff, WSJ, 24 May 2022 Volatile compounds can be smelled; nonvolatile ones can’t. Esther Mobley, San Francisco Chronicle, 2 Nov. 2017 SanDisk has been a long-term partner of Toshiba, with the two companies collaborating in the fabrication of nonvolatile memories, but is not seen as a front-runner in the auction. John Ribeiro, PCWorld, 14 May 2017
Caitlin Ostroff, WSJ, 24 May 2022 Volatile compounds can be smelled; nonvolatile ones can’t. Esther Mobley, San Francisco Chronicle, 2 Nov. 2017 SanDisk has been a long-term partner of Toshiba, with the two companies collaborating in the fabrication of nonvolatile memories, but is not seen as a front-runner in the auction. John Ribeiro, PCWorld, 14 May 2017 Word History
First Known Use
1844, in the meaning defined above
Medical Definition
nonvolatile
adjective
non·vol·a·tile
-ˈväl-ət-ᵊl, especially British -ə-ˌtīl
: not volatile