The affix yat comes in the sense of 'a collection' after the word vasu , as well as with the force of matup , in the chandas (Vedas).,
Thus वसव्यः = समूहः 'a collection'.
Vart:- The affix 'yat' comes without changing the sense, after the word छन्दस् when reference is made to the collection of letters. Thus the word छन्दस्यः in the following sentence: \सप्तादशाक्षरश्छन्दस्यः प्रजापतियज्ञो मन्त्रे विहिता\. The 17 letters here referred to being ओ श्रावय, four; अस्तु श्रौषट्, four; यज, two; ये यजामहे five; and वषट् two ॥
Vart:- The affix यत् comes after वसु without changing the sense. As हस्तौ गृहीतस्य बहुभिर्वसव्यैः ॥ Here वसव्यैः is equal to वसुभिः ॥ Similarly अग्निरीशे वसव्यस्य = वसोः ॥,