off·line / ˈôfˈlīn; ˈäf-/ (also off-line) Comput. • adj. not controlled by or directly connected to a computer or external network.• adv. (also off line) while not directly controlled by or connected to a computer or external network. ∎  with a delay between the production of data and its processing.

offline (or off-line) Of peripheral devices or files: not connected to the system or not usable. A device may be physically connected but offline if the system has been instructed not to use it.