Probably the name of a brahmin clan, the Agnivesyāyanas, and the Ksatriyas who were so styled, took the name from their brahmin purohitas (Further Dialogues, i.162 n).
The name is used by the Buddha in addressing Saccaka Niganthāputta (M.i.229f; 237f), and also Dīghanakha Paribbājaka (M.i.497f).
In the Dantabhūmi Sutta (M.iii.128f) the novice Aciravata is thus addressed by Prince Jayasena, who visits him, and also by the Buddha.