Definition of "alyssum" [alyssum]

• See sweet alyssum. (noun)
• Any of various chiefly Mediterranean weeds or ornamentals of the genus Alyssum in the mustard family, having racemes of white or yellow flowers. Also called madwort. (noun)
• See hoary alyssum. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Provide a mixture of nectar and seed rich flowering plants such as alyssum, sunflower and knapweed, which will attract insects and also provide seed for birds to feed on."
• "They take time to fill in, but shallow rooted annuals such as alyssum or impatiens can be seeded among them, reducing weeds and adding temporary color."
• "Sow certain things for succession, such as alyssum and mignonnette; and if you can spare a bit of reserve ground, sow there small patches of many annuals, ready for emergencies."