Some people believe that there is life after death, i.e., that our “soul” continues on in some sort of existence after our bodies cease to function and begin their inevitable decay.
Saying that they have this belief is the same as saying that they believe in an afterlife. The latter is much more concise way of saying it.
That having been said, some people believe in tooth fairies, Santa Claus and little green people from Mars. Saying that they believe this is the same as saying they are idiots, although “idiots” covers a lot more ground.
It’s only my opinion, but I suspect these people are no less correct in their beliefs than the people who believe in an afterlife. So, what does that say?
I’ve never heard it used this way before, but, according to the dictionary, afterlife can also be used to refer to a later period in someone’s life. This makes no sense to me. After life is death, not a later period in your corporeal life. Hence, this usage of afterlife makes no sense to me.
Then again, I’m getting old. I’m not particularly interested in having the first sense of afterlife. I’d imagine that eternity would get boring rather quickly. Besides, while we’re here who the hell wants to worry about what might come in the afterlife in the highly unlikely event there is one. And I do mean who the hell.
However, I would appreciate having plenty of years of the second sense of afterlife, provided they are healthy years.