Name him by return of post (4)

I believe the answer is:

liam

I'm a little stuck... Click here to teach me more about this clue!

'name him' is the definition.
'Liam' can be an answer for 'him'. I'm not certain of the 'name' bit.

'return of post' is the wordplay.
'return of' is a reversal indicator.
'post' becomes 'mail' (synonyms).
'mail' back-to-front is 'LIAM'.

'by' is the link.

Can you help me to learn more?

(Other definitions for liam that I've seen before include "Irishman" , "-- Neeson (actor)" , "Boy" .)

I've seen this clue in the Evening Standard.

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