transitive. To release.

To free (the lips, tongue, etc.) from constraint.

figurative. To free from the condition (or necessity) of remaining closed. (Cf. seal, v.1 6b)

transferred and figurative. Now only in the phrase to loosen (a person's) tongue, and in certain poetical or rhetorical uses (? after Shelley).

transitive. To let slip, set free.

transitive. = unloose, v. (in various senses). Also intransitive (cf. unloose, v. 5).