lupin (n.)

also lupine, flowering plant of the genus Lupinus, late 14c., from Latin lupinus, the name of the plant, a noun use of an adjective meaning "of a wolf," from lupus "wolf" (see wolf (n.)). The reason for the name is unclear; perhaps the plant was so called because of a belief that it was harmful to soil (compare lupus in the "wasting disease" sense), but in modern Europe it was regarded as useful and valued for improving sandy soil. In Portugal it was used to choke out weeds.