ailing
indisposed
peaked
poorly
sickly
unwell
under the weather
seedy

Not that she was happy to be under the weather, no.

She's pretty much under the weather but what's a man to do?

"My wife is feeling under the weather, so I need to get home early today."

The president had been feeling under the weather, it was revealed.

The man who seemed under the weather has been dead for six days.

You may be able to remain under the weather for months.

How many of you know people outside the hospital who are under the weather?

Good thing for you that I'm a little under the weather.

"He said you were feeling a bit under the weather."

You've had good reason to be a bit under the weather.