Tennyson Spencer Crowe was born early Friday at Sydney's Royal North Shore Private Hospital and weighed eight pounds (3.6 kilograms), the actor told Sydney radio station 2UE.
It is the second child for the celebrity couple and a brother for their firstborn, 2-year-old Charlie.
Asked why the couple chose the name, Crowe said: "My brother's name is Terry so that makes it (his initials) T.C. as well, so slightly after him. But mainly because it's just different."
The New Zealand-born, Australian-based actor said his wife was doing well after the birth.
He said the couple had been preparing their toddler to be a big brother, the AP reports
Crowe married Spencer in a star-studded Australian wedding in 2003.
Earlier this year, Crowe told U.S. TV talk show host Jay Leno that he and Spencer were expecting a boy, and that they had shared the news with their toddler son.