oftenest

from The Collaborative International Dictionary of English v.0.48
Often \Of"ten\ ([o^]f"'n; 115), adv. [Compar. {Oftener}
   ([o^]f"'n*[~e]r); superl. {Oftenest}.] [Formerly also ofte,
   fr. oft. See {Oft}., adv.]
   Frequently; many times; not seldom.
   [1913 Webster]
    

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