(Sanskrit; kappa in Pali) Maha means "great." Kalpa is a reference to an extended expanse of time, an age, or a "day of Brahma." Traditionally, it is said that there are four kalpas: formation, existence, destruction and emptiness (each portion is called asamkhyeya-kalpa). All four together are the lifespan of a world, and collectively are a complete cycle, called maha kalpa. Each of the four principle kalpas is subdivided into twenty antara-kalpas, or "small kalpas." There are different distinctions and illustrations of kalpas. In general, a small kalpa is represented as 16,800,000 years, a kalpa as 336,000,000 years and a mahakalpa is 1,334,000,000 years. Yet, these numbers are symbolic, not literal.
"Truthfully, the quantities of years assigned to a Cosmic Day are symbolic. The Cosmic Night arrives when the ingathering of the perfect souls is complete, which means, when the Cosmic Day is absolutely perfected." - Samael Aun Weor, The Pistis Sophia Unveiled