Mum one to stop the Spanish messages (1-4)
I believe the answer is:
'mum one to stop the spanish messages' is the definition.
I can't judge whether this defines the answer.
'mum one to stop the spanish' is the wordplay.
'mum' becomes 'ma' (ma can mean mother).
'one' becomes 'i' (Roman numeral).
'to stop' is an insertion indicator.
'the spanish' becomes 'el' ('the' in Spanish).
'ma'+'i'='mai'
'mai' put into 'el' is 'E-MAIL'.
Can you help me to learn more?
(Other definitions for e-mail that I've seen before include "Send a message" , "Electronic post" , "Online post" , "A lime (anag.)" , "Electronic message" .)