Webster's Revised Unabridged Dictionary · 1913

Loosen

Loosen (los"'n) , transitive verb

[See Loose, transitive verb]

1.
To make loose; to free from tightness, tension, firmness, or fixedness; to make less dense or compact; as, to loosen a string, or a knot; to loosen a rock in the earth.
After a year's rooting, then shaking doth the tree good by loosening of the earth. — Bacon
2.
To free from restraint; to set at liberty..
It loosens his hands, and assists his understanding. — Dryden
3.
To remove costiveness from; to facilitate or increase the alvine discharges of. — Bacon

Loosen , intransitive verb

To become loose; to become less tight, firm, or compact. — S. Sharp