Definition of johnny-jump-up:
(n) :
(Canada, US) Any of several violets or pansies.
(n) :
Viola tricolor (heartsease, wild pansy, pansy, et al.)
(n) :
Viola bicolor (American field pansy)
(n) :
Viola cornuta (tufted pansy)
(n) :
Viola pedunculata (California golden violet)
(n) :
Volatinia jacarina (blue-black grassquit bird)