be in a sweat
be in a ˈsweat
1 (also be all of a ˈsweat) (informal) be wet with sweat because it is hot or you have been running, etc: I had to run to work this morning because I got up late. I was in a real sweat when I arrived.
2 (also be in a cold ˈsweat) be very frightened or worried about something: I woke up during the night in a cold sweat worrying about the exam.
See also: sweat