Pradyumna: "Vyāsadeva is the original spiritual preceptor for all men, and all other preceptors are considered to be his representatives. A representative is one who can exactly present the viewpoint of Śrī Vyāsadeva. Śrī Vyāsadeva impregnated the message of Bhāgavatam unto Śrīla Śukadeva Gosvāmī, and Śrī Sūta Gosvāmī heard it from him, Śrīla Śukadeva Gosvāmī. All bona fide representatives of Śrī Vyāsadeva in the chain of disciplic succession are to be understood to be gosvāmīs. These gosvāmīs restrain all their senses, and they stick to the path made by the previous ācāryas."
Prabhupāda: Yes. Gosvāmī or svāmī, the same meaning: one who has been able to control the senses. Generally everyone is controlled by the senses. When one becomes controller of the senses, then he is gosvāmī. So generally we give this designation to the sannyāsīs, because sannyāsa means who has fully controlled all the senses. One should not accept sannyāsa whimsically. One must know about himself how far he can control the senses. Therefore generally sannyāsa is not accepted until one is sixty years old.
But in this age there is no guarantee whether we are going to live up to sixty years old age. So sometimes, younger generation also offered sannyāsa, because Caitanya Mahāprabhu accepted at the age of twenty-four years. We are not of course imitating Caitanya Mahāprabhu, but for executing Caitanya Mahāprabhu's mission, if we are sincerely working for Him, then we can take sannyāsa at an early age. That . . . when one is actually a sannyāsa, a sannyāsī, master of the senses, he can be addressed as gosvāmī or svāmī.