Webster's Revised Unabridged Dictionary · 1913

Expand

Expand , transitive verb

[Latin expandere, expansum; ex out + pandere to spread out, to throw open; perh. akin to English patent. Compare Spawn.]

1.
To lay open by extending; to open wide; to spread out; to diffuse; as, a flower expands its leaves.
Then with expanded wings he steers his flight. — Milton
2.
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 contract; as, to expand the chest; heat expands all bodies; to expand the sphere of benevolence.
3.
(Mathematics) To state in enlarged form; to develop; as, to expand an equation. See Expansion, 5.

Expand , intransitive verb

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