Whooped every so often, in Northern Ireland, during dance (7)
I believe the answer is:
hoedown
'dance' is the definition.
(I've seen this before)
'whooped every so often in northern ireland' is the wordplay.
'every so often' indicates alternate letters.
'in northern ireland' becomes 'down' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
The alternate letters of 'whooped' are 'hoe'.
'hoe'+'down'='HOEDOWN'
'during' acts as a link.
This may not be correct. It may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for hoedown that I've seen before include "Barn-dance" , "Lively folk dance (US)" , "American country dance" , "Lively steps" , "Boisterous American folk dance" .)