Meanings
How to pronounce "over one's head":
AU
More complex or confusing than one can understand; beyond one’s comprehension.
Example: "This is way over my head. Can you explain it more simply?"
More than one can handle; too much (especially in over one's head).
Example: "I’m in over my head on this project. Can you help?"
Performing at a level greatly superior to one's usual level of performance.
Example: "He just shot a spectacularly over his head round of golf and beat all of us."
Directed to someone with authority over the person, so as to avoid requiring the approval of the person himself or herself.
Used other than figuratively or idiomatically: see over, head.