unprecedentedly

from WordNet (r) 3.0 (2006)

unprecedentedly
    adv 1: in an unprecedented manner [ant: {precedentedly}]

from The Collaborative International Dictionary of English v.0.48

Unprecedented \Un*prec"e*dent*ed\, a.
   Having no precedent or example; not preceded by a like case;
   not having the authority of prior example; novel; new;
   unexampled. -- {Un*prec"e*dent*ed*ly}, adv.
   [1913 Webster]