The Collaborative International Dictionary
Improvingly
Improving \Im*prov"ing\, a. Tending to improve, beneficial; growing better. -- Im*prov"ing*ly, adv.
Improving lease (Scots Law), an extended lease to induce the tenant to make improvements on the premises.
Wiktionary
improvingly
adv. In a manner that tends to improve (especially, (context dated English), to educate or morally better a person).