vi to become sweet.
2. sweeten ·adj to soften to the eye; to make delicate.
3. sweeten ·adj to make sweet to the taste; as, to sweeten tea.
4. sweeten ·adj to make warm and fertile;
opposed to sour; as, to dry and sweeten soils.
5. sweeten ·adj to restore to purity; to free from taint; as, to sweeten water, butter, or meat.
6. sweeten ·adj to make mild or kind; to soften; as, to sweeten the temper.
7. sweeten ·adj to make pleasing or grateful to the mind or feelings; as, to sweeten life; to sweeten friendship.
8. sweeten ·adj to make less painful or laborious; to relieve; as, to sweeten the cares of life.
9. sweeten ·adj to make pure and salubrious by destroying noxious matter; as, to sweeten rooms or apartments that have been infected; to sweeten the air.