Pronunciation: (ik-spā'shē-āt"), [key]
—v.i., -at•ed, -at•ing.
1. to enlarge in discourse or writing; be copious in description or discussion: to expatiate upon a theme.
2. Archaic.to move or wander about intellectually, imaginatively, etc., without restraint.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.