Quotes:Manvantara

H. P. Blavatsky

Manvantara. A period of manifestation, as opposed to Pralaya (dissolution, or rest), applied to various cycles, especially to a Day of Brahmâ, 4,320,000,000 Solar years — and to the reign of one Manu — 308,448,000. (See Vol. II. of the Secret Doctrine, p. 68 et. seq.) Lit., Manuantara — between Manus.

Source: H. P. Blavatsky, The Theosophical Glossary, art. Manvantara