Amidst mayhem, I gratefully leave country (8)

I believe the answer is:

emigrate

I'm a little stuck... Click here to teach me more about this clue!

'leave country' is the definition.
(to emigrate is to leave one's country for another)

'amidst mayhem i gratefully' is the wordplay.
'EMIGRATE' is hidden in amongst the letters.
However, I'm unsure how the hidden word is indicated.

Can you help me to learn more?

(Other definitions for emigrate that I've seen before include "Go to live abroad" , "Move overseas" , "don't come back!" , "leave for ever" , "Permanently leave" .)

I've seen this clue in The Telegraph.

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