The definition of lifelong is something that will extend for the time that you are alive.
An example of lifelong is the relationship that you have with your children until you are dead.
Continuing for a lifetime.
- Extending for the entire duration of life.
- They were lifelong friends; they met in elementary school and ended their lives in the same rest home.
- It's a lifelong responsibility.
- The four men became lifelong friends and fellow-workers.
- The Henriade had got on considerably during the journey, and, according to his lifelong habit, the poet, with the help of his friend Thieriot and others, had been "working the oracle" of puffery.
- He played a slight part in the War of Independence, and was taken prisoner in 1781, her treatment resulting in a lifelong dislike of Great Britain.
- The two laughed and chattered like lifelong friends, perfectly comfortable in each other's company.