Plant Nomenclature 8 Family names are interchangeable

according to the International Code of Botanical Nomenclature:

Each of the eight exceptional names was almost universally used, and used in the same sense, throughout the world when the first edition of the Code was prepared and so, in accordance with the overriding goal of achieving nomenclatural stability, it was agreed that they would continue to be used. The eight names are

Gramineae (Grass Family, alternative Poaceae

Palmae (Palm Family, alternatively Arecaceae), 

Cruciferae (Mustard Family, alternatively Brassicaceae), 

Leguminosae (Pea family, alternatively Fabaceae), 

Guttiferae (St. John’s Wort Family, alternatively Clusiaceae), 

Umbelliferae (Carrot Family, alternatively Apiaceae), 

Labiatae (Mint Family, alternatively Lamiaceae), and 

Compositae (Daisy Family, alternatively Asteraceae).” (utah state herbarium)