Tell Pen, in secret, about something to discourage unwanted creatures (6,9)

I believe the answer is:

insect repellent

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'something to discourage unwanted creatures' is the definition.
I can't tell whether this definition defines the answer.

'tell pen in secret about' is the wordplay.
'about' indicates an anagram.
'tell'+'pen'+'in'+'secret'='tellpeninsecret'
'tellpeninsecret' anagrammed gives 'INSECT REPELLENT'.

Can you help me to learn more?

(Other definitions for insect repellent that I've seen before include "flies away with this?" , "Citronella, say" , "It deters pest" , "Lotion or spray against bites" .)

I've seen this clue in the Sydney Morning Herald.

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