The sacred call to Shambhala.
You mentioned to me the sacred call - Kalagiya! When someone hears this imperative call, he must know that the way to Shambhala is open to him. He must remember the year when he was called, because from that time evermore, he is closely assisted by the Blessed Rigden-jyepo. Only you must know and realize the manner in which people are helped, because often people repel the help which is sent. (S, 7)
Do not outrage the laws! Await in ardent labor until the messenger of Shambhala shall come to you, amid constant achievement. Await until the Mighty-voiced shall utter, ‘Kalagiya’. Then you may safely proceed to expound this superb matter. Vain curiosity must be transformed into sincere learning, into application to the high principles of everyday life. (S, 17)
I know that as a high spirit, already prepared, hears a voice proclaiming Kalagiya it is the call to Shambhala. (HIM, 30)

This definition is in context to Classic Yoga. See more contextual defintions for Kalagiya.