agapanthusPronunciation: /ˌagəˈpanθəs/Definition of agapanthus noun a South African plant of the lily family, with blue or white flowers growing in rounded clusters. Genus Agapanthus, family Liliaceae (or Alliaceae) Origin:modern Latin, from Greek agapē 'love' + anthos 'flower'agapanthus in other Oxford dictionaries Definition of agapanthus in the US English dictionary