merged in Durga...

वक्त्रं शीतकरोधरो घनरसः कामप्रदो विग्रहः 

श्वासो गन्धवहः सरोरुहसुहृत् पाणिः स्मिताभा शुचिः। 

वक्षः पीनपयोधराधिकरणं पृथ्वी नितंबस्थली 

तुष्टौ धूर्जटिमूर्त्तयः स्मरभयाद् दुर्गाश्रिताः पातु वः॥ 

vaktraṁ śītakarodharo ghanarasaḥ kāmaprado vigrahaḥ 

śvāso gandhavahaḥ saroruhasuhṛt pāṇiḥ smitābhā śuciḥ| 

vakṣaḥ pīnapayodharādhikaraṇaṁ pṛthvī nitaṁbasthalī 

tuṣṭau dhūrjaṭimūrttayaḥ smarabhayād durgāśritāḥ pātu vaḥ|| 

വക്ത്രം ശീതകരോധരോ ഘനരസഃ കാമപ്രദോ വിഗ്രഹഃ 

ശ്വാസോ ഗന്ധവഹഃ സരോരുഹസുഹൃത് പാണിഃ സ്മിതാഭാ ശുചിഃ। 

വക്ഷഃ പീനപയോധരാധികരണം പൃഥ്വീ നിതംബസ്ഥലീ 

തുഷ്ടൌ ധൂര്‍ജടിമൂര്‍ത്തയഃ സ്മരഭയാദ് ദുര്‍ഗാശ്രിതാഃ പാതു വഃ॥ 

It is a very famous concept that Lord Shiva Manifests in eight forms, and is called Astamoorthy for that reason

The eight forms are The Sun, The Moon, The Air, The fire, The sky, the Earth, the water and the living being who worships..

There is a famous story that Lord Shiva burnt down the God of love Kamadeva and went for a penance in the caves of Himalaya..

The Kamadeva, who is really tricky is pursuing Shiva relentlessly and trying to tempt Him to keep company of Uma.. Here in the sloka, it is described that Lord Shiva Split himself into eight forms and hid in the body of Durga the Parvathi..( we know about the Arthanari Form too) to escape any assault from Kamadeva 

Durga also means a distant fortress or cave, and so there is an allegory that Shiva hid in a fortress in eight forms to escape the attack of Kamadeva.

In this process, the form of Shiva.. Moon.. merged with Durgas face (वक्त्रं शीतकरः.. the face was occupied by the moon of soothingly cool raya 

The form of Shiva ... Water.. occupied Durga’s lips ( अधरः घनरसः the lips merged with water.. the essence of the clouds)

The form of Shiva as hota or the performer of sacrifice merged with Durga’s sweet body ( कामप्रदो विग्रहः the body which is the provider of all desires, merged with Durgas body) 

The form of Shiva as the Air merged with the breath of Durga ( श्वासो गन्धवहः the air which carries fragrance merged with the breath of Durga) 

The form of Shiva as the Sun merged with the hand of Durga ( सरोर्हसुहृत् पाणि the friend of the Lotus, the Sun merged with the hand of Durga) 

The form of Shiva as the Fire merged with the glowing smile of Durgaa (स्मिताभा शुचिः the glow of the smile merged with Shuchi.. the pure one..or the one who makes everything pure.. who is none other than fire)

The form of Shiva as the Sky merged with the ample bosom of Durga that carried very heavy breasts (अधिकरणम् पीनपयोधरः वक्षः .... the bosom with heavy breasts merged with the Adhikaranam or the sky)

The form of Shiva as the Earth merged with the slender waist area of Durga ( पृथ्वी नितम्ब स्थली the attractive waist area of Durga merged with the earth) 

एवं स्मरभयात् दुर्गाश्रिताः धूर्जटिमूर्तयः तुष्टौ (ते ) वः पातु thus the eight forms of that lord of terrific matted hair, Shiva, went and took refuge in the body of Durga, and were eternally happy.. May these forms protect you ever.

(1 Vaktram sheetakaraH 2 adharam ghanarasaH 3 Kamaprada vigrahaH 

4 ShvaasaH gandhavahaH 5paaniH saroruhasuhrit 6 Smitaabhaa suchi 7 peenapayodharaH vakshaH adhikaranam 8 nithambashtalee prithvee )