What is to become widely opened, spread apart, dilated, distended, or enlarged; as, flowers expand in the spring; metals expand by heat; the heart expands with joy. Dryden called?

expand — To become widely opened, spread apart, dilated, distended, or enlarged; as, flowers expand in the spring; metals expand by heat; the heart expands with joy. Dryden. (Webster's 1913.)

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