WordNet (r) 3.0 (2006):

cow cockle
    n 1: European annual with pale rose-colored flowers; cultivated
         flower or self-sown grainfield weed; introduced in North
         America; sometimes classified as a soapwort [syn:
         cowherb, cow cockle, Vaccaria hispanica, Vaccaria
         pyramidata, Saponaria vaccaria]