endless
adj.adj. seeming to have no end or limit. You use this to describe something that goes on for a very long time or covers a huge area.
adj. having or seeming to have no end, limit, or conclusion. Often used hyperbolically to describe repetitive tasks or vast physical spaces.
The children have endless energy even after playing all day.
We drove for hours across the endless plains without seeing a single house or tree.
The project was delayed by an endless series of bureaucratic hurdles that frustrated even the most patient members of the development team.
From Middle English endeles, from Old English endelēas (“endless”), from Proto-Germanic *andijalausaz (“endless”), equivalent to end + -less.
Typically used before a noun or after a linking verb; frequently functions as a hyperbolic intensifier.