Clue: Excited expression of character in Hamlet, not king or queen (6)
Answer: YOICKS
Explanation: Definition: Excited expression
A subtraction: YO[r]ICK'S ('of character in Hamlet' – of course, only his skull appears in the play; note the 'of' for the possessive 'S) minus the R ('not king or queen' – *Rex* or *Regina).