मननात्त्रायते यस्मात्तस्मान्मन्त्रः प्रकीर्त्तितः ।
mananāt trāyate yasmāt tasmān mantraḥ prakīrtitaḥ |
(Matsya-sūkta; cited in in Śabda-kalpa-druma)
“That by meditating upon which one is delivered is called a mantra [lit., ‘a means (tra) of meditation (man)’].”