DOUBLE-LOCK
Meaning of DOUBLE-LOCK in English
/dub"euhl lok"/ , v.t.
1. to lock with two turns of a key, so that a second bolt is engaged.
2. to fasten with particular care.
[ 1585-95 ]
Random House Webster's Unabridged English dictionary.
Полный английский словарь Вебстер - Random House .
2012