showing sustained enthusiastic action with unflagging vitality; "an indefatigable advocate of equal rights"; "a tireless worker"; "unflagging pursuit of excellence"
not capable of being conquered or vanquished or overcome; "a tribute to his courage...and his unconquerable will"- R.E.Danielson; "faced unconquerable difficulties"
people who are old collectively; "special arrangements were available for the aged"
(used of tobacco) aging as a preservative process (`aged' is pronounced as one syllable)
of wines, fruit, cheeses; having reached a desired or final condition; (`aged' pronounced as one syllable); "mature well-aged cheeses"
advanced in years; (`aged' is pronounced as two syllables); "aged members of the society"; "elderly residents could remember the construction of the first skyscraper"; "senior citizen"
at an advanced stage of erosion (pronounced as one syllable); "aged rocks"
existing for a long time; "hopes for a durable peace"; "a long-lasting friendship"
very long lasting; "less durable rocks were gradually worn away to form valleys"; "the perdurable granite of the ancient Appalachian spine of the continent"
serviceable for a long time; "durable denim jeans"
stubbornly unyielding; "dogged persistence"; "dour determination"; "the most vocal and pertinacious of all the critics"; "a mind not gifted to discover truth but tenacious to hold it"- T.S.Eliot; "men tenacious of opinion"
characterized by care and perseverance in carrying out tasks; "a diligent detective investigates all clues"; "a diligent search of the files"
quietly and steadily persevering especially in detail or exactness; "a diligent (or patient) worker"; "with persevering (or patient) industry she revived the failing business"