Alternative form of God knows, in sense of something unknown to mortal men.

(idiomatic) Alternative form of time will tell

Alternative spelling of read-only memory

Alternative form of if only the tsar knew

(computing) A computer memory chip that stores values but does not allow updates, in which the values are nonvolatile in that they are retained even when the computer is unpowered.

(idiomatic, almost always preceded by the) The only opportunity, activity, or resource available.

plural of only game in town.

A market at which vendors may only sell items which they or their employees produce.

plural of producer-only market

The situation where an event is so well attended, or public transportation so full, that all of the seats in the venue are occupied, leaving only the ground or the floor for other people.