(1)永久的でない
(2)持続しない
(3)not permanent; not lasting; "politics is an impermanent factor of life"- James Thurber; "impermanent palm cottages"; "a temperary arrangement"; "temporary housing"
さらに詳しく
(1)注意や当然と思われる関心が欠如していること
(2)lack of attention and due care