La*bur"num (?), n. [L.] Bot.
A small leguminous tree (Cytisus Laburnum), native of the Alps. The plant is reputed to be poisonous, esp. the bark and seeds. It has handsome racemes of yellow blossoms.
⇒ Scotch laburnum (Cytisus alpinus) is similar, but has smooth leaves; purple laburnum is C. purpureus.
© Webster 1913.