Compulsion to put on nursing uniform (6)
I believe the answer is:
duress
'compulsion' is the definition.
(as in doing something under duress)
'put on nursing uniform' is the wordplay.
'put on' becomes 'dress' (to dress is to put on clothes).
'nursing' indicates putting letters inside.
'uniform' becomes 'U' (phonetic alphabet: alpha, bravo, charlie etc.).
'dress' enclosing 'u' is 'DURESS'.
'to' is the link.
(Other definitions for duress that I've seen before include "Restraint" , "Coercion, pressure" , "Constraint, coercion" , "Threat of coercion" , "Hardship" .)