An avandiya is a person unworthy of reverence, who can fall into the following categories:
- Younger than oneself.
- Elderly, "unrighteous", and living in a different residence.
- Unordained.
- Female.
- Eunuch.
- Parivasika
- Mulayapatikassanaraha
- Manattaraha
- Manatacarika
- Abbanaraha
The elderly men of one's residence, "righteous" elderly men of other residences, and the Buddha are always to be revered.
A monk becomes an avandiya if he is indiscreet with the bhikkuni. This is decided by a danda-kamma meeting of the bhikkuni sangha. (Note the interesting contrast here: this is from the same text, Cullavagga, but in this section the female monks are given the power rather than having the honor taken away from them.)