The heir of the French crown under the Valois and Bourbon dynasties. Guy VIII., Count of Vienne, was the first so styled, because he wore a dolphin as his cognisance. The title descended in the family till 1349, when Humbert II., de la tour de Pisa, sold his seigneurie, called the Dauphiné, to King Philippe VI. (de Valois), on condition that the heir of France assumed the title of le dauphin. The first French prince so called was Jean, who succeeded Philippe; and the last was the Duc d'Angoulême, son of Charles IX., who renounced the title in 1830.
Second or Little Dauphin. Louis, son of the Grand Dauphin. (1682-1712.)
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894