1.To make sweet to the taste; as, to sweeten tea.
2.To make pleasing or grateful to the mind or feelings; as, to sweeten life; to sweeten friendship.
3.To make mild or kind; to soften; as, to sweeten the temper.
4.To make less painful or laborious; to relieve; as, to sweeten the cares of life. "And sweeten every secret tear."
5.To soften to the eye; to make delicate. "Correggio has made his memory immortal by the strength he has given to his figures, and by sweetening his lights and shadows, and melting them into each other."
6.To make pure and salubrious by destroying noxious matter; as, to sweeten rooms or apartments that have been infected; to sweeten the air.
7.To make warm and fertile; opposed to sour; as, to dry and sweeten soils.
8.To restore to purity; to free from taint; as, to sweeten water, butter, or meat.
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