The affix ṅvanip comes after the verbs su 'to press out or extract juice' and yaj 'to sacrifice', with a past signification.,
As सु + ङ्वनिप् = सुत् + वन् (VI. I 71) = सुत्वन् 1st. sing. सुत्वा 'who has pressed out or extracted juice'; यज्वन्, 1st. sing. यज्वा 'who has sacrificed'. The त् is added by 6.1.71. See Rig. Ved. 1.3.1.,