under the weather

US /ˈʌndər ðə ˈwɛðər/
UK /ˈʌndər ðə ˈwɛðər/
"under the weather" picture
1.

体調が悪い, 気分が優れない

feeling slightly ill or unwell

:
I'm feeling a bit under the weather today, so I might go home early.
今日は少し体調が悪いので、早く帰るかもしれません。
She's been under the weather for a few days, so she hasn't come to work.
彼女は数日間体調が悪いので、仕事に来ていません。