knock sth off (sth)

— Phrasal Verb with knock

/nɒk/ verb [T]

Definition

informal

› to take a particular amount away from a price, value, etc.: Living next door to an empty home can also knock 10% off the value of your own property, say experts. Customers can knock hundreds of dollars off their energy bills by following three simple steps. The supermarket joined the fuel price war yesterday by knocking 5 cents a liter off its petrol and diesel prices.

(Definition of knock sth off (sth) from the Cambridge Business English Dictionary © Cambridge University Press)