What is the difference between 'life time' and 'lifetime' or life-time ?

Question

What is the difference between 'life time' and 'lifetime' or life-time ?

Answer 1

lifetime: life: the period during which something is functional (as between birth and death); "the battery had a short life"; "he lived a long and happy life"

life time: which takes place in real-time as the surgeons perform an operation that must be completed within 22 minutes

life-time: refer to definition 1, usually the - helps people to read better like a comma.

Answer 2

lifetime is one word.

Answer 3

Lifetime is correct. It's one word.

Answer 4

"Lifetime" is the most acceptable version, though you will see other versions being used-wrongly-in many magazines and lesser publications.