Noah Webster
Expatiate
EXPA'TIATE, verb intransitive [Latin expatior; ex and spatior, to wander, to enlarge in discourse, spatium, space, probably allied to pateo, to open.
1. To open at large; to rove without prescribed limits; to wander in space without restraint.
He bids his soul expatiate in the skies.
Expatiate free o'er all this scene of man.
2. To enlarge in discourse or writing; to be copious in argument or discussion. On important topics the orator thinks himself at liberty to expatiate