goose

/guːs/ noun [C]

Definition

the goose that lays the golden egg(s) › the thing that makes you the most money: The fuel and energy sector is the goose that lays the golden eggs.

kill the goose that lays the golden egg(s) › to destroy the thing that makes you the most money, or stop it from making money: Raising entry prices to tourist attractions will kill the goose that lays the golden egg for this town. No-one will come here any more.

(Definition of goose noun from the Cambridge Business English Dictionary © Cambridge University Press)