to increase in extent, size, volume, scope, etc.: Heat expands most metals. He hopes to expand his company.
to spread or stretch out; unfold: A bird expands its wings.
to express in fuller form or greater detail; develop: to expand a short story into a novel.
Mathematics. to write (a mathematical expression) so as to show the products of its factors. Compare factor (def 10). to rewrite (a mathematical expression) as a sum, product, etc., of terms of a particular kind: to expand a function in a power series.
to increase or grow in extent, bulk, scope, etc.: Most metals expand with heat. The mind expands with experience.