Expert more or less puts up with losing northern operations (10)

'operations' is the definition.
('procedure' can be a synonym of 'operation')

'expert more or less puts up with losing northern' is the wordplay.
'expert' becomes 'pro' (I've seen this before).
'more or less' becomes 'c' (abbreviation for 'circa', meaning approximately).
'puts up with' becomes 'endures' ('endure' can be a synonym of 'put up with').
'losing' is a deletion indicator.
'northern' becomes 'n' (abbreviation e.g. N. Ireland).
'endures' with 'n' taken away is 'edures'.
'pro'+'c'+'edures'='PROCEDURES'