yasya tac chrotram ucyate
vāyor guṇa-viśeṣo ’rtho
yasya tat sparśanaṁ viduḥ
nabhaḥ-guṇa-viśeṣaḥ—the distinctive characteristic of sky (sound); arthaḥ—object of perception; yasya—whose; tat—that; śrotram—the auditory sense; ucyate—is called; vāyoḥ guṇa-viśeṣaḥ—the distinctive characteristic of air (touch); arthaḥ—object of perception; yasya—whose; tat—that; sparśanam—the tactile sense; viduḥ—they know.
The sense whose object of perception is sound is called the auditory sense, and that whose object of perception is touch is called the tactile sense.
Sound is one of the qualifications of the sky and is the subject matter for hearing. Similarly, touch is the qualification of the air and is the subject of the touch sensation.
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