The facilities at Harvard Law School included lockable and unlockable carrels and lockable rooms. The lockable carrels and rooms were limited in number and were assigned to students by priority based on age.1980, Commerce Clearing House, Tax court memorandum decisions: Volume 38:
Casters can be swivel, rigid, lockable, or unlockable.2003, David E. Mulcahy, John Dieltz, Order fulfillment and across the dock concepts, design operations handbook, page 172:
Video games An initially hidden feature that is made available to reward the player for some achievement.
But usually when people refer to the metagame, they mean things such as unlockables or customizable features.2012, Keith Burgun, Game Design Theory: A New Philosophy for Understanding Games, CRC Press, →ISBN, page 98:
unlockable
adj
Etymology From unlock + -able.
1
Capable of being unlocked.
This unlockable demo allows customers to use the full-featured product free for seven days.1998, Brent D Heslop, David A Holzgang, HTML Publishing on the Internet: