Source : Webster's Revised Unabridged Dictionary (1913)

Live-forever \Live"-for*ev`er\, n. (Bot.)
   A plant ({Sedum Telephium}) with fleshy leaves, which has
   extreme powers of resisting drought; garden ox-pine.

Source : WordNet®

live-forever
     n : perennial northern temperate plant with toothed leaves and
         heads of small purplish-white flowers [syn: {orpine}, {orpin},
          {livelong}, {Sedum telephium}]