Under the Weather

Someone said to be "under the weather" is someone who appears to be at less than full health, like a sky that is cloudy instead of clear. The person can either be ill, or intoxicated; the important thing is that the person is not feeling well. Ex.: "Arnold looks under the weather. Maybe he's having a bad reaction to the mussels he ate last night?" Mussels are a type of sea food; people not used to eating them will sometimes get seriously ill due to sensitivity to particular bacteria. A milder reaction may merely make someone feel under the weather.