Tantra

rgyud - [alt.] being, mind, stream, a) continuity, being b) Tantra. abbr. {rgyud} Mahayoga. 1) tantra, tantra-texts, being [body, speech and mind], stream of being, mind-stream, continuity, continuum, "linked together", area, location, stream of existence, mind, heart, nature, existence. 2) the tantric teachings, texts. 3) via, through [sm. {brgyud}. 4) bank, shore, coast, edge, side, range. 5) lineage, descent. 6) area, location. 6) individual, person 7) bow string {mdo rgyud} sutra and tantra]. 8) continuum [or continua], tantra, string, cord. mind-stream; tantra/ continuum; mind-stream [RY]

See (gsang sngags rdo rje theg pa rgyud) - tantrayana, tantra, esoteric or inner teachings of the Mahayana vehicle, the secret and sublime adamantine / vajra vehicle of Secret Mantra, Vajrayana [RY]