Āchamanam (Sanskrit: आचमनम्, ācamanam) is a purification ritual performed at the beginning of more complex religious ceremonies in the Hinduism, which is believed to cure all physical and mental impurities.
ācamanam trividham - śrautaṃ smārtaṃ paurāṇaṃ cetitatra pratyakṣaśruticoditaṃ śrautam, sūtroktaṃ smārtamkeśavādyaistribhiḥ pītveti vacanoktaṃ paurāṇam[3] Achamana is of three types - Śrautā, Smārta (as directed by Smritis) and Paurāṇā (as per Puranas).There Śrautācamanam is directly instructed by Śruti (i.e. Vedas), Smārtācamanam is formulated by dharmasūtras (i.e. Smṛti).Sippping (of water) thrice with the (24) names (of Vishnu) starting with keśava is called PaurāṇācamanamHowever, in the Sandhyavandana ritual, there exists fourth version of āchamana, known as mantrācamana.
It is defined in ṣatkarma candrikā as[5] devyāḥ pādaistribhiḥ pītvā abliṅgairnvabhiḥ spṛśetsaptavyāhṛtisaṃyuktā gāyatrī tripadā śiraḥ[note 5]-ṣatkarma candrikāThe Smṛtyācamanam is an abridged version of the śrautācamanam.
Then, 9 parts of the body are touched, accompanied by recitation of the specific sutras that instruct the version of the achamana in question.
[note 6] The water is poured on the right hand palm, which made as gokurna sipped thrice with the first three names.