Pronunciation: (lOO'sun), [key]
1. to unfasten or undo, as a bond or fetter.
2. to make less tight; slacken or relax: to loosen one's grasp.
3. to make less firmly fixed in place: to loosen a tooth.
4. to let loose or set free from bonds, restraint, or constraint.
5. to make less close or compact in structure or arrangement.
6. to make less dense or coherent: to loosen the soil in a garden.
7. to relax in strictness or severity, as restraint or discipline: to loosen restrictions on trade.
8. to relieve (the bowels) of their constipated condition.
to become loose or looser (sometimes fol. by up): His hold loosened. Your shoes will loosen up with wear.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.