Samhita literally means "put together, joined, union", a "collection", and "a methodically, rule-based combination of text or verses". Samhita also refers to the most ancient layer of text in the Vedas, consisting of mantras, hymns, prayers, litanies and benedictions.
Samhita is a Sanskrit word from the prefix sam (सम्), 'together', and hita (हित), the past participle of the verbal root dha (धा) 'put'.  The combination word thus means "put together, joined, compose, arrangement, place together, union", something that agrees or conforms to a principle such as dharma or in accordance with justice, and "connected with". Saṃhitā (संहिता) in the feminine form of the past participle, is used as a noun meaning "conjunction, connection, union", "combination of letters according to euphonic rules", or "any methodically arranged collection of texts or verses".
Samhita, however, in contemporary literature typically implies the earliest, archaic part of the Vedas. These contain mantras – sacred sounds with or without literal meaning, as well as panegyrics, prayers, litanies and benedictions petitioning nature or Vedic deities. Vedic Samhita refer to mathematically precise metrical archaic text of each of the Vedas (Rigveda, Yajurveda, Samaveda and Atharvaveda).
The Vedas have been divided into four styles of texts – the Samhitas (mantras and benedictions), the Aranyakas (text on rituals, ceremonies, sacrifices and symbolic-sacrifices), the Brahmanas (commentaries on rituals, ceremonies and sacrifices), and the Upanishads (text discussing meditation, philosophy and spiritual knowledge). The Samhitas are sometimes identified as karma-khanda (कर्म खण्ड, action/ritual-related section), while the Upanishads are identified as jnana-khanda (ज्ञान खण्ड, knowledge/spirituality-related section). The Aranyakas and Brahmanas are variously classified, sometimes as the ceremonial karma-khanda, other times (or parts of them) as the jnana-khanda.
A collective study of Vedas and later text suggests that the compendium of Samhitas and associated Vedic texts were far larger than currently available. However, most have been lost at some point or over a period of Indian history.
- ॐ भूर्भुवस्वः। तत्सवितुर्वरेण्यम्। भर्गो देवस्य धीमहि। धियो यो नः प्रचोदयात्
- Oṁ Bhūr Bhuva~Swah', Tat savitur varenyam, Bhargo devasya dhīmahi, Dhiyo yo nah prachodayāt
Weber noted that the Samhita of Samaveda is an anthology taken from the Rigveda-Samhita. The difference is in the refinement and application of arts such as melody, meters of music and literary composition. Thus, the root hymn that later became the Rathantara (Excellent Chariot) mantra chant is found in both Rigveda and Samaveda Samhitas, as follows,
- Rigveda form: Abhi tva sura nonumo 'dugdha iva dhenavah | isanam asya jagatah svardrsam isanam indra tasthusah
- Samaveda form: obhitvasuranonumova | adugdha iva dhenava isanamasya jagatassuvardrsam | isanama indra | ta sthu sa o va ha u va | as ||
May the Vasus prepare you, with the gayatri meter, you are the earth,
May the Rudras prepare you, with the tristubh meter, you are the sky.
May the Adityas prepare you, with the jagati meter, you are the heaven.
May the Visvedevas, common to all men, prepare you, with the anustubh meter, you are the directions.
You are the unchanging direction, make unchanging in me children, abundance of wealth, abundance of cattle, abundance of heroism.
May O Agni!, a suitor after this girl's heart come to her,
May he come to this maiden with fortune!
May she be agreeable to suitors, charming at festivals, promptly obtain happiness through a husband!
There are many well known books written in the post-vedic period, also known as samhitas, because the word “samhita” also means “systematic compilation of knowledge”. Vedic samhitas should not be confused with these samhitas of post-vedic period.
Some post-vedic Samhitas are: Ashtavakra Gita, Bhrigu Samhita, Brahma Samhita, Charaka Samhita, Deva Samhita, Garga Samhita, Gheranda Samhita, Kashyap Samhita, Shiva Samhita, Sushruta Samhita (a treatise on food and medicine), Yogayajnavalkya Samhita.
- saMhita, Monier-Williams' Sanskrit-English Dictionary, Oxford University Press, page 1123
- Gavin D. Flood (1996). An Introduction to Hinduism. Cambridge University Press. p. 37. ISBN 978-0-521-43878-0.
- Lochtefeld, James G. "Samhita" in The Illustrated Encyclopedia of Hinduism, Vol. 2: N-Z, Rosen Publishing, ISBN 0-8239-2287-1, page 587
- Samhita, Merriam Webster Etymology (2008), Quote: "Sanskrit samhita, literally, combination, from sam together + hita, past participle of dadhati he puts, places"
- Surendranath Dasgupta (1922). A History of Indian Philosophy. Motilal Banarsidass. p. 12. ISBN 978-81-208-0412-8.
- Friedrich Max Müller (1891). The Sacred Books of the East. Clarendon Press. p. xlii.
- A Bhattacharya (2006), Hindu Dharma: Introduction to Scriptures and Theology, ISBN 978-0595384556, pages 8-14
- Jan Gonda (1975), Vedic Literature: (Saṃhitās and Brāhmaṇas), Otto Harrassowitz Verlag, ISBN 978-3447016032
- Gavin Flood (1996), An Introduction to Hinduism, Cambridge University Press, ISBN 978-0521438780, pages 35-37
- See Shankara's Introduction at Google Books to Brihad Aranyaka Upanishad at pages 1-5; Quote - "The Vedas are divided in two parts, the first is the karma-khanda, the ceremonial part, also (called) purva-khanda, and treats on ceremonies; the second part is the jnana khanda, the part which contains knowledge, also named uttara-khanda or posterior part, and unfolds the knowledge of Brahma or the universal soul." (Translator: Edward Roer)
- Stephen Knapp (2005), The Heart of Hinduism: The Eastern Path to Freedom, Empowerment and Illumination, ISBN 978-0595350759, pages 9-16
- Monier Monier-Williams (1893), Indian Wisdom, Luzac & Co., London, page 17
- Edward F Crangle (1994), The Origin and Development of Early Indian Contemplative Practices, Otto Harrassowitz Verlag, ISBN 978-3447034791, page 124
- Albrecht Weber, History of Indian Literature, Samaveda-Samhita at Google Books, page 63
- Frits Staal (2009), Discovering the Vedas: Origins, Mantras, Rituals, Insights, Penguin, ISBN 978-0143099864, pages 107-115
- Harvey P. Alper (2012), Understanding Mantras, Motilal Banarsidass, ISBN 978-8120807464, pages 75-76
- Edward F Crangle (1994), The Origin and Development of Early Indian Contemplative Practices, Otto Harrassowitz Verlag, ISBN 978-3447034791, page 32
- Atharva Veda Samhita, Book 2 Hymn 36: To get a husband for a woman, Translator: William Dwight Whitney, Atharva Veda Samhita Series - Harvard University (Editor: Charles Rockwell Lanman), Wikisource
- Rajbali Pandey (1969), Hindu Saṁskāras: Socio-religious Study of the Hindu Sacraments, Motilal Banarsidass, ISBN 978-8120803961, pages 162-163