The Collaborative International Dictionary
Oftensith
Oftensith \Of"ten*sith\ ([o^]f"'n*s[i^]th`), adv. [Often + sith time.] Frequently; often. [Obs.]
For whom I sighed have so oftensith.
--Gascoigne.
Wiktionary
oftensith
adv. (context obsolete English) frequently; often