adverb, adverb taking the 'to' particle
remarkably; noticeably; considerably
Describes a clear, often sudden change in degree or state, especially a decline or increase that is easy to perceive. Commonly used with verbs like 減る, 増える, 寒くなる, 涼しくなる.
When autumn came, it became noticeably cooler.
Lately, I've seen him around considerably less.
Now that it's autumn, it has become noticeably colder.
Lately, the number of customers has noticeably decreased.
He has aged noticeably over the past year.