(a.) Without old age limits of duration; as, fountains of ageless youth.

age-old ancient antique auld ceaseless coeternal constant continual continuous dateless elderly endless eternal eterne ever-being ever-durable ever-during everlasting everliving hoary immemorial incessant indestructible infinite interminable never-ceasing never-ending nonstop nonterminating nonterminous of old of yore olamic old old as Methuselah old as history old as time old-time olden perdurable permanent perpetual sempiternal steady timeless unceasing unending unintermitting uninterrupted unremitting venerable without end