The onion belongs to which plant family?

Allium cepa L., or the garden onion, is not the sweetest smelling flower in the lily family, and has been accused of bringing some of us to tears. The allium genus of the liliaceae family, however, contains some very tasty members that are staples in many cuisines the world over. Onions are part of the mirepiox (celery, carrots and onions) in traditional French cuisine, as well as the “holy trinity” (bell peppers, onions, celery) in Cajun cuisine. Used raw and cooked, onions and their relatives lend their flavors to many popular dishes.