PURPORT

Srila Bhaktisiddhanta Sarasvati Thakura quotes his notes from the Nataka-candrika, wherein he has written:

prastavanayas tu mukhe
nandi karyasubhavaha
asir-namaskriya-vastu-
nirdesanyatamanvita

astabhir dasabhir yukta
kimva dvadasabhih padaih
candranamaṅkita prayo
maṅgalartha-padojjvala
maṅgalam cakra-kamala-
cakora-kumudadikam

Similarly, in the Sixth Chapter of the Sahitya-darpana, text 282, he has said:

asir-vacana-samyukta
stutir yasmat prayujyate
deva-dvija-nr-padinam
tasman nanditi samjnita

The introductory portion of a drama, which is written to invoke good fortune, is called nandi-sloka.