Manusmriti

siva.sh/manusmriti/9/138

पुन्नाम्नो नरकाद् यस्मात् त्रायते पितरं सुतः । तस्मात् पुत्र इति प्रोक्तः स्वयमेव स्वयम्भुवा ॥ १३८ ॥

sanskrit

Because a son delivers (trayate) his father from the hell called Put, he was therefore called put-tra (a deliverer from Put) by the Self-existent (Svayambhu) himself.

english translation

punnAmno narakAd yasmAt trAyate pitaraM sutaH | tasmAt putra iti proktaH svayameva svayambhuvA || 138 ||

hk transliteration by Sanscript