bean trefoil

from The Century Dictionary.

• noun The laburnum, Cytisus Laburnum, a leguminous shrub with trifoliate leaves. See laburnum.
• noun The Anagyris fœtida, a similar shrub of southern Europe, whose violet-colored seeds are said to be poisonous like those of the laburnum.
• noun The buckbean, Menyanthes trifoliata.

from the GNU version of the Collaborative International Dictionary of English.

• (Bot.) A leguminous shrub of southern Europe, with trifoliate leaves (Anagyris foetida).

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Anagyris foetida, a leguminous shrub of southern Europe with trifoliate leaves.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun shrub with trifoliate leaves and yellow flowers followed by backward curving seed pods; leaves foetid when crushed