One splashing out, acquiring American garter in Boston? (9)

I believe the answer is:

suspender

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'garter in boston?' is the definition.
'suspender' can be an answer for 'garter' (thesaurus). I'm unsure of the 'in boston?' bit.

'one splashing out acquiring american' is the wordplay.
'one splashing out' becomes 'spender' (I can't justify this - if you can you should believe this answer much more).
'acquiring' is an insertion indicator.
'american' becomes 'US' (United States).
'spender' placed around 'us' is 'SUSPENDER'.

Can you help me to learn more?

(Other definitions for suspender that I've seen before include "Supporter" , "material support" , "Sock support" , "Strap to hold up a stocking" , "It upholds" .)

I've seen this clue in The Telegraph.

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