Barnum and Bailey were flashy fellows! (7)

I believe the answer is:

showmen

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'barnum and bailey' is the definition.
I can't judge whether this definition defines the answer.

'flashy fellows' is the wordplay.
'flashy' becomes 'show' (I can't explain this - if you can you should believe this answer much more).
'fellows' becomes 'men' (fellow can mean a man).
'show'+'men'='SHOWMEN'

'were' acts as a link.

Can you help me to learn more?

I've seen this clue in the Evening Standard.

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