Source : Webster's Revised Unabridged Dictionary (1913)

Vetchling \Vetch"ling\, n. [Vetch + -ling.] (Bot.)
   Any small leguminous plant of the genus {Lathyrus},
   especially {L. Nissolia}.

Source : WordNet®

vetchling
     n : any of various small plants of the genus Lathyrus; climb
         usually by means of tendrils