work (your) arse/backside off

British & Australian, very informal, American, very informal

to work very hard.

My father worked his backside off to pay for our education.

• not give a toss
• not give someone house room
• not give someone the time of day
• not give something a second thought
• not give something house room
• not give the time of day
• not give tuppence
• not go a bundle on
• not go a bundle on something
• not go amiss
• not hack it
• Not half!
• not half
• not half bad
• no thanks to
• no thanks to someone
• no thanks to something
• not have a bean
• not have a bone in body
• tow the line
• toy boy
• to your face
• to your fingertips
• to your heart's content
• toy with