Bother sister over savings scheme before church (8)
I believe the answer is:
nuisance
'bother' is the definition.
(I know that nuisance is a type of bother)
'sister over savings scheme before church' is the wordplay.
'sister' becomes 'nun' (sister is a term of address for a nun).
'over' means one lot of letters goes inside another.
'savings scheme' becomes 'isa' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'before' means one lot of letters go next to another.
'church' becomes 'CE' (abbreviation for Church of England).
'nun' enclosing 'isa' is 'nuisan'.
'nuisan'+'ce'='NUISANCE'
Can you help me to learn more?
(Other definitions for nuisance that I've seen before include "Bother" , "'Pest, annoyance (8)'" , "Source of irritation, person or thing" , "Bothersome annoying person" , "Pest, source of annoyance" .)