dateless

形容词 dateless:

1. having no known beginning and presumably no end
   同义词：endless, sempiternal
2. of such great duration as to preclude the possibility of being assigned a date
3. not bearing a date
   同义词：undated
4. unaffected by time
   同义词：timeless

date.less

adj.（形容词）
Having no date whatsoever.
无日期的，未注明日期的：无论什么都没有日期的
So ancient that no date can be determined.
年代不可考的：古老得无法确定日期的
Having no limits in time; timeless.
没有时间限制的；永恒的