The disciple (monk) who is a prospective Ācārya (preceptor) and who, after having studied the Sūtra (2) (canonical aphorism) and its meaning, undertakes visits to various countries as per his guru's instructions, in order to acquire information relating to conduct, languages etc...
ye sūtrārthau gṛhītvā bhaviṣyadācāryā gurūṇāmupadeśena viṣayā" cārabhāsopalambhanimittamāhiṇḍante te upadeśāhiṇḍkāḥ.
(BṛBhā 5825 Vṛ)