immortellePronunciation: /ˌɪmɔːˈtɛl/Definition of immortelle noun 1another term for everlasting (sense 2 of the noun). 2West Indian a Caribbean tree of the pea family, with a spiny trunk and clusters of red, orange, or pinkish flowers. Genus Erythrina, family Leguminosae: two species Origin:French (feminine adjective), literally 'everlasting'immortelle in other Oxford dictionaries Definition of immortelle in the US English dictionary