Lose pants in northern new town (6)
I believe the answer is:
nelson
'town' is the definition.
(I have seen 'northern town' mean 'nelson' so perhaps 'town' could also mean 'nelson')
'lose pants in northern new' is the wordplay.
'pants' indicates an anagram (UK informal term for 'nonsense' or 'rubbish').
'in' indicates putting letters inside.
'northern' becomes 'n' (abbreviation e.g. N. Ireland).
'new' becomes 'n' (abbreviation as in New Testament NT).
'lose' with letters rearranged gives 'elso'.
'n'+'n'='nn'
'elso' going inside 'nn' is 'NELSON'.
(Other definitions for nelson that I've seen before include "Admiral called 5" , "Sailor" , "Admiral; wrestling hold" , "one visibly affected by fighting" , "Emma Hamilton's lover, who died in battle on 21 October 1805" .)