What is 1. To make lighter, or less heavy; to reduce in weight; to relieve of part of a load or burden; as, to lighten a ship by unloading; to lighten a load or burden called?

lighten — 1. To make lighter, or less heavy; to reduce in weight; to relieve of part of a load or burden; as, to lighten a ship by unloading; to lighten a load or burden. (Webster's 1913.)

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