What is to make right or correct; to reduce to order; as, to straighten one's affairs; to straighten an account. To straighten one's face, to cease laughing or smiling, etc., and compose one's features called?

straighten — To make right or correct; to reduce to order; as, to straighten one's affairs; to straighten an account. To straighten one's face, to cease laughing or smiling, etc., and compose one's features. (Webster's 1913.)

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