इति वैष्णवपुराणे ।'व्यूह्यात्मानं चतुर्धा वै वासुदेवादिमूर्तिभिः ।सृष्ट्यादीन् प्रकरोत्येष विश्रुतात्मा जनार्दनः' इति व्यासवचनात् चतुर्व्यूहः ।दंष्ट्राश्चतस्रो यस्येति चतुर्दंष्ट्रः नृसिंहविग्रहः ।
In plain words
As stated in the Vaishnava Purana, according to the words of Vyasa: 'Having divided Himself fourfold through the forms beginning with Vasudeva, the renowned Janardana performs creation and cosmic functions'—hence He is Caturvyuha. Having four fangs, Caturdamshtra, in the ferocious form of Narasimha.
Close to the Sanskrit
In the Vaishnava Purana. From the statement of Vyasa: 'Having manifested Himself in a fourfold manner through forms beginning with Vasudeva, this renowned Janardana performs creation and other acts'—hence Caturvyuha. Having four fangs, Caturdamṣhtra, in the Narasimha incarnation.