What does "expand" mean?

Expand: To cause the particles or parts of to spread themselves or stand apart, thus increasing bulk without addition of substance; to make to occupy more space; to dilate; to distend; to extend every way; to enlarge; -- opposed to Ant: contract; as, to expand the chest; heat expands all bodies; to expand the sphere of benevolence.

Additional senses

  1. 2.(Math.) To state in enlarged form; to develop; as, to expand an equation. See Expansion, 5.
  2. 3.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.

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