welsh onion: Asiatic onion with slender bulbs; used as early green onions
onion: bulbous plant having hollow leaves cultivated worldwide for its rounded edible bulb
selenium: a toxic nonmetallic element related to sulfur and tellurium; occurs in several allotropic forms; a stable grey metallike allotrope conducts electricity better in the light than in the dark and is used in photocells; occurs in sulfide ores (as pyrite)