Ancient coin southern engineer found under compound (8)

I believe the answer is:

sesterce

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'ancient coin' is the definition.
'sesterce' can be an answer for 'coin' (I have seen 'antique coin' mean 'sesterce' so perhaps 'coin' could also mean 'sesterce'). I am unsure of the 'ancient' bit.

'southern engineer found under compound' is the wordplay.
'southern' becomes 's' (abbreviation).
'engineer' becomes 'ce' (abbreviation for civil engineer).
'found under' says to put letters next to each other.
'compound' becomes 'ester' (ester is a kind of compound).
'ce' put after 'ester' is 'esterce'.
's'+'esterce'='SESTERCE'

Can you help me to learn more?

(Other definitions for sesterce that I've seen before include "antique coin" , "MONEY" .)

I've seen this clue in The Times.

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