The phrase "one's only job" means a single responsibility or duty that someone has been assigned to do. It refers to something that is expected from an individual and they are responsible for completing it successfully.
Sentences with «one's only job»
Looking for a job is not only a job in and of itself, it's expensive. (distinctiveweb.com)
I received some advice from someone whose only job in life is to take money from «greedy» landlords and give it to «deserving» and «abused» tenants. (biggerpockets.com)
We believe in the transformative power of the everyday dog or cat — «ordinary» companion pets whose only job in life is to love without limits. (petsforpatriots.org)