verb
-ens; -ened; -ening
[+ obj] :to make (something) less tight or firm :to make (something) loose or looser
[no obj] :to become less tight or firm :to become loose or looser
to become or to cause (something) to become less strict [+ obj]
loosen someone's tongue
to cause someone to talk more freely :to cause someone to say things that would not usually be said
loosen up
[phrasal verb]
to make or become less tense :relax
loosen (someone or something) up or loosen up (someone or something) :to cause (someone or something) to relax