Interpret former patent (7)

I believe the answer is:

explain

'interpret' is the definition.
(I know that interpret is a more specific form of explain)

'former patent' is the wordplay.
'former' becomes 'ex' (prefix meaning former or onetime).
'patent' becomes 'plain' (synonyms).
'ex'+'plain'='EXPLAIN'

(Other definitions for explain that I've seen before include "Make (something) clear" , "Tell us how" , "Elucidate, clarify" , "Make intelligible and account for" , "Spell out" .)

I've seen this clue in The Telegraph.

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