also: だいぶん
Indicates a significant degree or amount, often with a sense of 'more than expected'. Used with adjectives, verbs, and nouns.
だいぶ寒くなってきたね。
It's gotten considerably colder, hasn't it?
Your Japanese has improved a lot, hasn't it?
My fever has come down considerably.
My Japanese has gotten a lot better.
It takes quite a while to get to the station.
The number of participants has increased considerably.
Alternate reading, slightly more emphatic or dialectal. Often written in kana.