Row about Ulster being less significant (6)
I believe the answer is:
tinier
'less significant' is the definition.
I can't judge whether this definition defines the answer.
'row about ulster' is the wordplay.
'row' becomes 'tier' (a tier is a row of things).
'about' means one lot of letters goes inside another.
'ulster' becomes 'NI' (Northern Ireland).
'tier' going around 'ni' is 'TINIER'.
'being' acts as a link.
Can you help me to learn more?
(Other definitions for tinier that I've seen before include "Much smaller" , "Smaller than Dicken's Tim?" , "more minute?" , "Even smaller" , "much less significant?" .)