Cast a milkman and ex-actor! (11,4)
I believe the answer is:
exclamation mark
'cast a milkman and ex-actor' is the definition.
I can't tell whether this definition defines the answer.
'cast a milkman and ex-actor' is the wordplay.
'cast' indicates anagramming the letters (letters are dispersed or cast around).
'and' says to put letters next to each other.
'a'+'milkman'+'ex'+'actor'='amilkmanexactor'
'amilkmanexactor' with letters rearranged gives 'EXCLAMATION MARK'.
Can you help me to learn more?
(Another definition for exclamation mark that I've seen is " With surprising completion of sentence".)