What is to make worse; to make inferior in quality or value; to impair; as, to deteriorate the mind. Whately. The art of war . . . was greatly deteriorated. Southey called?

deteriorate — To make worse; to make inferior in quality or value; to impair; as, to deteriorate the mind. Whately. The art of war . . . was greatly deteriorated. Southey. (Webster's 1913.)

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