What does the word "flah" mean in Irish slang?

[Iloko]

wanna hear the explanation from actual Irish people born or raised in Ireland thx..

[Grace O'Malley]

wanna hear the explanation from actual Irish people born or raised in Ireland thx..

I think you mean fleadh which is a festival with singing and dancing etc.

You can hear it pronounced here.

https://en.oxforddictionaries.com/definition/fleadh