Man in suit failing to start Yankee’s guaranteed payment (7)

I believe the answer is:

annuity

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'guaranteed payment' is the definition.
(I've seen this before)

'man in suit failing to start yankee's' is the wordplay.
'man in' becomes 'annu' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'suit' becomes 'fit' (synonyms).
'failing to start' means to remove the first letter.
'yankee' becomes 'Y' (phonetic alphabet: alpha, bravo, charlie etc.).
'fit' with its initial letter removed is 'it'.
'annu'+'it'+'y'='ANNUITY'

Can you help me to learn more?

(Other definitions for annuity that I've seen before include "Pension investment" , "Regular income from a fund" , "Yearly allowance" , "regular payment" , "Form of investment" .)

I've seen this clue in The Times.

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