Im*prov"ing*ly

from The Collaborative International Dictionary of English v.0.48

Improving \Im*prov"ing\, a.
   Tending to improve, beneficial; growing better. --
   {Im*prov"ing*ly}, adv.
   [1913 Webster]

   {Improving lease} (Scots Law), an extended lease to induce
      the tenant to make improvements on the premises.
      [1913 Webster]