lychnisPronunciation: /ˈlɪknɪs/Definition of lychnis noun a plant of a genus which includes the campions, ragged robin, and a number of cultivated ornamental flowers. Genus Lychnis, family Caryophyllaceae Origin:modern Latin, via Latin from Greek lukhnis, denoting a red flower, from lukhnos 'lamp'lychnis in other Oxford dictionaries Definition of lychnis in the US English dictionary