Collins Chinese Dictionary Plus (3rd edition), 2011:
considerably [k&n'sId&r&blI] adv [improve, vary] 在很大程度上 zài hěn dà chéngdù shang
[bigger, smaller etc] 相当(當)地 xiāngdāng de
在这些条目还发现'considerably':
在英文解释里:
a great deal - much less - much more - quite