The Collaborative International Dictionary of English v.0.48:

Wake-robin \Wake"-rob`in\, n. (Bot.)
   Any plant of the genus Arum, especially, in England, the
   cuckoopint (Arum maculatum).
   [1913 Webster]

   Note: In America the name is given to several species of
         Trillium, and sometimes to the Jack-in-the-pulpit.
         [1913 Webster]

WordNet (r) 3.0 (2006):

wake-robin
    n 1: any liliaceous plant of the genus Trillium having a whorl
         of three leaves at the top of the stem with a single three-
         petaled flower [syn: trillium, wood lily, wake-robin]
    2: common American spring-flowering woodland herb having
       sheathing leaves and an upright club-shaped spadix with
       overarching green and purple spathe producing scarlet berries
       [syn: jack-in-the-pulpit, Indian turnip, wake-robin,
       Arisaema triphyllum, Arisaema atrorubens]