Poke one's nose in and enter if upset about queen (9)
I believe the answer is:
interfere
'poke one's nose in' is the definition.
(I've seen this before)
'enter if upset about queen' is the wordplay.
'upset' indicates anagramming the letters.
'about' means one lot of letters goes inside another.
'queen' becomes 'er' (abbreviation for Elizabeth Regina).
'enter'+'if'='enterif'
'enterif' anagrammed gives 'intfere'.
'intfere' going around 'er' is 'INTERFERE'.
'and' is the link.
(Other definitions for interfere that I've seen before include "Poke one's nose in" , "Attempt" , "Obstruct, pry" , "Meddle, poke into" , "Meddle, butt in" .)