The word "reincarnation" derives from Latin, literally meaning, "entering the flesh again". The Greek equivalent metempsychosis (μετεμψύχωσις) derives from meta (change) and empsykhoun (to put a soul into), a term attributed to Pythagoras. An alternate term is transmigration implying migration from one life (body) to another. Reincarnation refers to the belief that an aspect of every human being (or all living beings in some cultures) continues to exist after death, this aspect may be the soul or mind or consciousness or something transcendent which is reborn in an interconnected cycle of existence; the transmigration belief varies by culture, and is envisioned to be in the form of a newly born human being, or animal, or plant, or spirit, or as a being in some other non-human realm of existence. The term has been used by modern philosophers such as Kurt Gödel and has entered the English language. Another Greek term sometimes used synonymously is palingenesis, "being born again".
Rebirth is a key concept found in major Indian religions, and discussed with various terms. Punarjanman (Sanskrit: पुनर्जन्मन्) means "rebirth, transmigration". Reincarnation is discussed in the ancient Sanskrit texts of Hinduism, Buddhism, and Jainism, with many alternate terms such as punarāvṛtti (पुनरावृत्ति), punarājāti (पुनराजाति), punarjīvātu (पुनर्जीवातु), punarbhava (पुनर्भव), āgati-gati (आगति-गति, common in Buddhist Pali text), nibbattin (निब्बत्तिन्), upapatti (उपपत्ति), and uppajjana (उप्पज्जन). These religions believe that this reincarnation is cyclic and an endless Saṃsāra, unless one gains spiritual insights that ends this cycle leading to liberation. The reincarnation concept is considered in Indian religions as a step that starts each "cycle of aimless drifting, wandering or mundane existence", but one that is an opportunity to seek spiritual liberation through ethical living and a variety of meditative, yogic (marga), or other spiritual practices. They consider the release from the cycle of reincarnations as the ultimate spiritual goal, and call the liberation by terms such as moksha, nirvana, mukti and kaivalya. However, the Buddhist, Hindu and Jain traditions have differed, since ancient times, in their assumptions and in their details on what reincarnates, how reincarnation occurs and what leads to liberation.
Gilgul, Gilgul neshamot or Gilgulei Ha Neshamot (Heb. גלגול הנשמות) is the concept of reincarnation in Kabbalistic Judaism, found in much Yiddish literature among Ashkenazi Jews. Gilgul means "cycle" and neshamot is "souls". Kabbalistic reincarnation says that humans reincarnate only to humans and to the same sex only: men to men, women to women.