Expand meaning : To change (something) from a smaller form and/or size to a larger one; to spread out or lay open. To increase the extent, number, volume or scope of (something). To express (something) at length and/or in detail. To rewrite (an expression) as a longer, yet equivalent sum of terms. (of an expression) To become, by rewriting, a longer, yet equivalent sum of terms. To multiply both the numerator and the denominator of a fraction by the same natural number yielding a fraction of equal value To change from a smaller form/size to a larger one. To increase in extent, number, volume or scope. To speak or write at length or in detail. To feel generous or optimistic.