Sloka 

त्वदीयं सौन्दर्यं निरतिशयमालोक्य परया
भियैवासीद्गङ्गा जलमयतनुः शैलतनये ।
तदेतस्यास्तस्माद्वदनकमलं वीक्ष्य कृपया
प्रतिष्ठामातन्वन्निजशिरसिवासेन गिरिशः ॥ 18॥


tvadīyaṃ saundaryaṃ niratiśayamālōkya parayā
bhiyaivāsīdgaṅgā jalamayatanuḥ śailatanayē ।
tadētasyāstasmādvadanakamalaṃ vīkṣya kṛpayā
pratiṣṭhāmātanvannijaśirasivāsēna giriśaḥ ॥ 18॥


த்வதீ³யம் ஸௌந்த³ர்யம் நிரதிஶயமாலோக்ய பரயா
பி⁴யைவாஸீத்³க³ங்கா³ ஜலமயதனு: ஶைலதனயே ।
ததே³தஸ்யாஸ்தஸ்மாத்³வத³னகமலம் வீக்ஷ்ய க்ருபயா
ப்ரதிஷ்டா²மாதன்வன்னிஜஶிரஸிவாஸேன கி³ரிஶ: ॥ 18॥

Audio Link 

https://drive.google.com/file/d/1VJgblUQIekdeDMQSg6T7I79IohX-ADr3/view?usp=drivesdk

Padacheda (Word Separation)

त्वदीयम् सौन्दर्यम् निरतिशयम् आलोक्य परया

भिया एव आसीत् गङ्गा जल-मय-तनुः शैल-तनये ।

तत् एतस्याः तस्मात् वदन-कमलम् वीक्ष्य कृपया

प्रतिष्ठाम् आतन्वन् निज-शिरसि वासेन गिरिशः ॥

Anvaya (Prose Order)

हे शैलतनये, त्वदीयं निरतिशयं सौन्दर्यम् आलोक्य परया भिया एव गङ्गा जलमयतनुः आसीत्। तस्याः वदनकमलं वीक्ष्य कृपया गिरिशः निजशिरसि वासेन तस्याः प्रतिष्ठाम् आतन्वन्।

Meaning of the Words 

त्वदीयं सौन्दर्यं - tvadīyaṃ saundaryaṃ - your beauty
निरतिशयमालोक्य - niratiśayamālōkya = niratiśayam + ālokyā - unsurpassed/incomparable.+ having seen
परया भियैवासीद्गङ्गा - parayā bhiyaivāsīdgaṅgā = परया + भिया + एव + आसीत् + गङ्गा - paraya bhiyā - with great fear  + eva -indeed  + āsīt - was + gaṅgā - Gaṅgā
जलमयतनुः - jalamayatanuḥ = जल-मय-तनुः - jala-maya-tanuḥ: whose body is made of water (The poet imagines Gaṅgā becoming so overwhelmed by the Goddess’s beauty that she is reduced, poetically, to her essential nature as water). 
शैलतनये - śailatanayē - śaila-tanaye: O daughter of the mountain

तदेतस्यास्तस्माद्वदनकमलं  - tadētasyāstasmādvadanakamalaṃ = तत् एतस्याः तस्मात् वदन-कमलम्  - tad-etasya: तत् — then / that एतस्याः — of this one / of her (In context, एतस्याः refers to Gaṅgā.) + तस्मात् = therefore / for that reason / from that + वदनकमलम् = “lotus-like face” / “lotus-face” (of Ganga) 
वीक्ष्य कृपया - vīkṣya kṛpayā - वीक्ष्य = “having seen”, “having beheld” + कृपया = “out of compassion”, “through compassion”.

प्रतिष्ठामातन्वन्निजशिरसिवासेन - pratiṣṭhāmātanvannijaśirasivāsēna
प्रतिष्ठाम् = “a place of establishment / an established position” + आतन्वन् = “extending”, “establishing”, “providing” + निजशिरसि = “upon his own head.” + वासेन = “by residence”, “through giving residence”

गिरिशः - giriśaḥ गिरिशः = “Lord of the Mountain”, i.e. Śiva.

தமிழாக்கம்

ஈடிணையிலா உன்னெழில் வடிவு கண்ட கங்கை
பீதிமிகு வியப்புடனே நீர் வடிவமேற்றதைக் கண்டு, மலைமகளே
இரக்கமுடன் திருமுடியிலே இடமளித்தான் இமயநாதன் !! 18

Meaning 

Having seen your unsurpassed incomparable beauty, O daughter of the mountain, Ganga took the form of water, overcome by supreme awe. And taking mercy for her lotus like face seized with such fear [of being compared unfavorably], the Lord of the mountains Śiva, gave her a place of honour upon His own head.

God Bless