endless is an adjective that describes something that is infinite and continuous. It is used to describe the seemingly infinite length of time and space, and can be used in both literal and figurative senses.
1. The starry sky stretched out into an endless expanse.
2. He entered into an endless loop of contemplation.
3. The hike seemed to go on forever, with no end in sight.
when used as an adjective, endless is usually used together with other words, such as 'endless sky' or 'endless loop'.