To do with stress inside erratic ticker? (5)

I believe the answer is:

ictic

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'to do with stress' is the definition.
I can't tell whether this definition defines the answer.

'inside erratic ticker?' is the wordplay.
'inside' indicates a hidden word.
'ICTIC' is hidden in the letters of 'erratic ticker'.

Can you help me to learn more?

(Another definition for ictic that I've seen is " being subject to stress".)

I've seen this clue in The Independent.

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