14. (To be) Under the weather
Can you be under the weather literally? Probably yes, if you think about standing under the clouds, rain and sun, but it makes no sense. If you’re feeling under the weather, you’re not your usual self and could be feeling a little sick. The sick feeling is nothing serious; perhaps it’s just extreme tiredness from studying too much, or having a bad headache because you’re starting to get the flu.
“What’s wrong with Katy, mom?”
“She’s feeling a little under the weather so be quiet and let her rest.”