Webster's Revised Unabridged Dictionary · 1913

Unaccustomed

Unaccustomed , adjective

1.
Not used; not habituated; unfamiliar; unused; -- with to.
Chastened as a bullock unaccustomed to the yoke. — Jer. xxxi. 18
2.
Not usual; uncommon; strange; new.
What unaccustomed cause procures her hither? — Shakespeare