Terribly idle lad rang (7)
I believe the answer is:
dialled
'rang' is the definition.
'terribly idle lad' is the wordplay.
'terribly' is an anagram indicator.
'idle'+'lad'='idlelad'
'idlelad' anagrammed gives 'DIALLED'.
(Other definitions for dialled that I've seen before include "Rang (a number)" , "Telephoned" .)
I've seen this clue in The Telegraph.
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