Krishnamantra, Kṛṣṇamantra, Krishna-mantra: 5 definitions
Introduction:
Krishnamantra means something in Hinduism, Sanskrit. If you want to know the exact meaning, history, etymology or English translation of this term then check out the descriptions on this page. Add your comment or reference to a book if you want to contribute to this summary article.
The Sanskrit term Kṛṣṇamantra can be transliterated into English as Krsnamantra or Krishnamantra, using the IAST transliteration scheme (?).
In Hinduism
Purana and Itihasa (epic history)
Kṛṣṇamantra (कृष्णमन्त्र) refers to the “mantra of Kṛṣṇa”, according to the Śivapurāṇa 2.5.27 (“The birth of Śaṅkhacūḍa”).—Accordingly, [while narrating the story of Dambha, grandson of Danu and sage Kaśyapa]: “[...] No son was born to [Dambha]. Hence the hero became worried. He made the preceptor Śukra his initiator and learnt the mantra of Kṛṣṇa [e.g., kṛṣṇamantra]. He performed a great penance in the holy centre Puṣkara for a hundred thousand years. Seating himself in a stable pose he performed the Japa of Kṛṣṇa mantra for a long time. While be was performing the penance, an unbearable refulgence sprang up blazing from his head and spread everywhere. All the gods, sages and Manus were scorched by that. With Indra ahead they sought refuge in Brahmā. [...]”;
Kṛṣṇamantra (कृष्णमन्त्र).—As a shield against all dangers; combined with vaiṣṇavatejas and śiva-śakti.*
- * Brahmāṇḍa-purāṇa III. 31. 37-8.

The Purana (पुराण, purāṇas) refers to Sanskrit literature preserving ancient India’s vast cultural history, including historical legends, religious ceremonies, various arts and sciences. The eighteen mahapuranas total over 400,000 shlokas (metrical couplets) and date to at least several centuries BCE.
Vaishnavism (Vaishava dharma)
Kṛṣṇamantra (कृष्णमन्त्र) refers to:—The gopāla-mantra of which Śrī kṛṣṇa is the predominating deity;received at the time of dīkṣā. (cf. Glossary page from Arcana-dīpikā).

Vaishnava (वैष्णव, vaiṣṇava) or vaishnavism (vaiṣṇavism) represents a tradition of Hinduism worshipping Vishnu as the supreme Lord. Similar to the Shaktism and Shaivism traditions, Vaishnavism also developed as an individual movement, famous for its exposition of the dashavatara (‘ten avatars of Vishnu’).
Pancaratra (worship of Nārāyaṇa)
1) Kṛṣṇamantra (कृष्णमन्त्र) [=Śrīkṛṣṇamantra] is the name of a Mantra (i.e., “śrīṃ hrīṃ klīṃ kṛṣṇāya svāhā”), as discussed in the fourth chapter [first book] of the Jñānāmṛtasārasaṃhita: a Pāñcarātra text representing a sectarian glorification of Kṛṣṇa and Rādha (i.e., the cult of Radha-Krishna) dated among the latest of the Saṃhitā-type works.—Description of the chapter [brahmanāradasaṃvāde kavacapraśaṃsā]: Continuing the story of Subhadra, Brahmā tells how that Brahmin boy was visited by the sage Nārāyaṇa who initiated the lad with the Śrī-Kṛṣṇamantra (“śrīṃ hrīṃ klīṃ kṛṣṇāya svāhā”). The boy is also given a necklace containing an amulet (of this mantra?) (1-36 ). [...]
2) Kṛṣṇamantra (कृष्णमन्त्र) is the name of a Mantra discussed in the fifteenth chapter of the Parāśarasaṃhitā: a Pañcarātra work of some 2000 verses dealing withe the composition and applications of Mantras, the characteristics of devotees (prapanna) and initiation.—Description of the chapter [haṃsamatsyādi-mantravidhi]: This chapter turns to the mantras attached to each of the ten avatāras and some other forms—the nyāsas appropriate, the japa-repetitions, the gāyatrī-forms, the bīja-analyses, etc.—[For example]:—kṛṣṇamantra ( 248-271 ), yantra for kṛṣṇa (272-290), holy places suitable for repetition of kṛṣṇamantra (291-297), general rules for using kṛṣṇamantra (298-300). [...] The remainder of the chapter (301-313) deals with differences between the various mantras and their respective sub-varieties.
3) Kṛṣṇamantra (कृष्णमन्त्र) refers to one of the Mantras addressed to the several avatāra-forms of the Lord, as discussed in chapter 27 (Caryāpāda) of the Padmasaṃhitā: the most widely followed of Saṃhitā covering the entire range of concerns of Pāñcarātra doctrine and practice (i.e., the four-fold formulation of subject matter—jñāna, yoga, kriyā and caryā) consisting of roughly 9000 verses.—Description of the chapter [matsyādi-mūrtimantra-kathana]: Bhagavān continues to tell about mantras in this chapter, turning now to the mantras addressed to the several avatāra-forms of the Lord. In each, the analysis of the mantra-composition is given, along with instructions for japa-repetitions, as well as other details. The mantras discussed here are: [e.g., kṛṣṇamantra and its variations (331b-421)] [...]

Pancaratra (पाञ्चरात्र, pāñcarātra) represents a tradition of Hinduism where Narayana is revered and worshipped. Closeley related to Vaishnavism, the Pancaratra literature includes various Agamas and tantras incorporating many Vaishnava philosophies.
Languages of India and abroad
Sanskrit dictionary
Kṛṣṇamantra (कृष्णमन्त्र) as mentioned in Aufrecht’s Catalogus Catalogorum:—Rādh. 25.
Sanskrit, also spelled संस्कृतम् (saṃskṛtam), is an ancient language of India commonly seen as the grandmother of the Indo-European language family (even English!). Closely allied with Prakrit and Pali, Sanskrit is more exhaustive in both grammar and terms and has the most extensive collection of literature in the world, greatly surpassing its sister-languages Greek and Latin.
See also (Relevant definitions)
Partial matches (+0): Krishna, Mantra.
Full-text (+3): Krishnayantra, Haridhama, Mantrarajanyasa, Mantravidhi, Mantranamarahasya, Mantranama, Namarahasya, Mahamantra, Shunashira, Mantrarajanyasanirupana, Naradopadesha, Naradopadeshagrahana, Avapya, Lakshavarshaka, Lakshavarsha, Baddhasana, Bhaktijnananirupana, Bhaktijnana, Gandharvamokshana, Upavarhana.
Relevant text
Search found 25 books and stories containing Krishnamantra, Krishna-mantra, Krishna-mantras, Kṛṣṇa-mantra, Krsna-mantra, Kṛṣṇamantra, Krsnamantra; (plurals include: Krishnamantras, mantras, mantrases, Kṛṣṇamantras, Krsnamantras). You can also click to the full overview containing English textual excerpts. Below are direct links for the most relevant articles:
Krishna Sandarbha of Jiva Goswami (by Kusakratha Prabhu)
Brahma Samhita (Jiva Goswami commentary) (by Srila Narayana Maharaja)
A Descriptive Catalogue of the Sanskrit Manuscripts, Madras (by M. Seshagiri Sastri)
Notices of Sanskrit Manuscripts (by Rajendralala Mitra)
Brihad Bhagavatamrita (commentary) (by Śrī Śrīmad Bhaktivedānta Nārāyana Gosvāmī Mahārāja)
Verse 1.1.12 < [Chapter 1 - Bhauma (the earthly plane)]
Verse 2.3.125 < [Chapter 3 - Bhajana (loving service)]