The affix ḍāc comes after the word madra followed by kṛ 'to make' in the sense of 'to shave'.,
The word परिवापण means 'to shave' 'to raze'. The word मद्र means 'auspicious'. Thus मङ्गलं मुण्डनं करोति = मद्रा करोति ॥
Vart:- So also after the word भद्रा; as भद्रा करोति नापितं कुमारं \the barber shaves the hair of the boy on the auspicious occasion\.
Why do we say when meaning 'to shave'. Observe मद्रं or भद्रं करोति ॥,