loosen

verb ! Definition from Wiktionary (CC BY-SA). Pronunciation from Wiktionary, via Kaikki.org. More about loosen at Wordnik → Where our words come from →

1. To make loose.

   to loosen a knot; to loosen one's grip / hold on something

2. To become loose.

   I noticed that my seatbelt had gradually loosened during the journey.

3. To disengage (a device that restrains).