liner lock

Noun

 * 1) A type of lock for a folding knife or other tool that is locked open/extended by a spring portion of the liner, which must be pushed down by the thumb before the knife or tool can be closed/collapsed.
 * 2)  A knife or other tool with such a lock.

Translations

 * Danish:
 * Finnish: liner lock -veitsi
 * German: Liner-Lock
 * Russian:
 * Swedish: liner lock-kniv