in the thick of something/of doing something
in the thick of it
Very busy; in the middle of or preoccupied with something or several things. Sorry I couldn't make it to your birthday lunch on Wednesday, I'm afraid I'm really in the thick of it at the office right now. Even when you are in the thick of it, try to take a moment each day and take a deep, calming breath.
in the thick of it
orin the thick of something
COMMON If you are in the thick of it or in the thick of an activity or situation, you are very involved in it. Soon he was in the thick of it, chatting in three languages, kissing hands, explaining and introducing. He suddenly found himself in the thick of desperate fighting.
in the ˈthick of something/of doing something
1 in the busiest or most active part of something/doing something: He was in the thick of preparing the food for the party, so I didn’t interrupt.
2 in the most crowded part of something: If there’s trouble, you usually find him in the thick of it.