Being exhausted with tango, one missed sign of swelling? (7)

I believe the answer is:

redness

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'tango one missed sign of swelling?' is the definition.
I can't judge whether this defines the answer.

'being exhausted with' is the wordplay.
'being' becomes 'red' (red is a kind of being).
'exhausted with' becomes 'ness' (I can't justify this - if you can you should believe this answer much more).
'red'+'ness'='REDNESS'

Can you help me to learn more?

(Other definitions for redness that I've seen before include "Inflamed appearance" , "Appearance of inflammation" .)

I've seen this clue in The Telegraph.

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