पादबद्धोऽक्षरसमस्तन्त्रीलयसमन्वितः।
शोकार्तस्य प्रवृत्तो मे श्लोको भवतु नान्यथा॥
pāda-baddho ’kṣara-samas tantrī-laya-samanvitaḥ
śokārtasya pravṛtto me śloko bhavatu nānyathā
pāda-baddhaḥ = with four quarters; akṣara-samaḥ = each with an equal number of syllables; tantrī-laya-samanvitaḥ = and capable of being sung to stringed musical accompaniment with a rhythmic tempo; śoka-ārtasya = saddened by distress; pravṛttaḥ = when was; me = I; ślokaḥ = a śloka; bhavatu = be known as; na anyathā = and nothing else.
[Let the utterance that came from me] when I was saddened by distress with four quarters, each with an equal number of syllables, and capable of being sung to stringed musical accompaniment with a rhythmic tempo be known as a śloka and nothing else!
When Śrī Vālmīki was distressed by the lamentation of a female krauñca bird, he had uttered a verse—a śloka—that could be sung to the accompaniment of a vīṇā and other musical instruments.