The affix ac comes after the words 1. vasīyas and 2. śreyas when they follow the word śvas in a compound.,
Thus श्वोवसीयसम्, श्वःश्रेयसम् ॥ These compounds belong to the class of Mayuravyansakadi 2.1.72 The word श्वः is usually employed in blessing or praising the object expressed by the second term. Thus श्वः श्रेयसम् ते भूयात् = शोभनं श्रेयस्ते भूयात् ॥ The word श्वोवसीयसम् is a synonym of श्वः श्रेयसम् ॥ The word वसीयः is derived from वसु meaning \praiseworthy\, \rich\, by adding the affix ईयसुन् 5.3.57.,