English Noun Joseph's flower (plural Joseph's flowers) (archaic) A flower, Tragopogon pratensis. Synonym: Jack-go-to-bed-at-noon References “Joseph's flower”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC. Wikiwand - on Seamless Wikipedia browsing. On steroids.