wikipedia - Mantra (Sanskrit मन्त्र) means a sacred utterance, numinous sound, or a syllable, word, phonemes, or group of words believed by some to have psychological and spiritual power. Mantra may or may not be syntactic or have literal meaning; the spiritual value of mantra comes when it is audible, visible, or present in thought.
The Sanskrit word mantra- (m.; also n. mantram) consists of the root man- "to think" (also in manas "mind") and the suffix -tra, designating tools or instruments, hence a literal translation would be "instrument of thought".

Scholars consider mantras to be older than 1000 BC. By the middle Vedic period - 1000 BC to 500 BC - claims Frits Staal, mantras in Hinduism had developed into a blend of art and science to include verses, saman, yajus, and nigada.
The Chinese translation is zhenyan 眞言, 真言, literally "true words", the Japanese on'yomi reading of the Chinese being shingon (which is also used as the proper name for the prominent esoteric Shingon sect).
According to Schlerath, the concept of sātyas mantras is found in Indo-Iranian Yasna 31.6 and Rigveda, where it means more than 'true Word', it is considered formulated thought which is in conformity with the reality or poetic (religious) formula with inherent fulfillment.
Mantras are neither unique to Hinduism, nor to other Indian religions such as Buddhism; similar creative constructs developed in Asian and Western traditions as well. Mantras, suggests Staal, may be older than language.
The Sanskrit word mantra- (m.; also n. mantram) consists of the root man- "to think" (also in manas "mind") and the suffix -tra, designating tools or instruments, hence a literal translation would be "instrument of thought".

Scholars consider mantras to be older than 1000 BC. By the middle Vedic period - 1000 BC to 500 BC - claims Frits Staal, mantras in Hinduism had developed into a blend of art and science to include verses, saman, yajus, and nigada.
The Chinese translation is zhenyan 眞言, 真言, literally "true words", the Japanese on'yomi reading of the Chinese being shingon (which is also used as the proper name for the prominent esoteric Shingon sect).
According to Schlerath, the concept of sātyas mantras is found in Indo-Iranian Yasna 31.6 and Rigveda, where it means more than 'true Word', it is considered formulated thought which is in conformity with the reality or poetic (religious) formula with inherent fulfillment.
Mantras are neither unique to Hinduism, nor to other Indian religions such as Buddhism; similar creative constructs developed in Asian and Western traditions as well. Mantras, suggests Staal, may be older than language.