What is to form a scum; to become covered with scum. Also used figuratively. Life, and the interest of life, have stagnated and scummed over. A. K. H. Boyd called?

scum — To form a scum; to become covered with scum. Also used figuratively. Life, and the interest of life, have stagnated and scummed over. A. K. H. Boyd. (Webster's 1913.)

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