vãi

• (Hà Nội) IPA^(key): [vaːj˦ˀ˥]
• (Huế) IPA^(key): [vaːj˧˨]
• (Hồ Chí Minh City) IPA^(key): [vaːj˨˩˦] ~ [jaːj˨˩˦]

From Middle Vietnamese uãi, vãi, from Proto-Vietic *vaːs (“to broadcast (rice)”). Cognate with Tho [Cuối Chăm] vɐːl⁶, Chut [Rục] vaːl⁶.

Unrelated to Chinese 播 (MC puɑ^H) (SV: bá) nor any Austroasiatic word with labial stop initial like Khmer បោះ (bɑh), Khasi bet. As shown by the Vietic cognates, Vietnamese ‹v-› here is not the result of lenition.

vãi • (捤, 𢭶)

1. to spill (something) all over; to strew; to broadcast
2. (of rice, seeds, etc.) to be spilled all over; to be scattered
3. to excrete (involuntarily); to let out; to urinate or pee (by accident)

vãi

1. (slang, vulgar) extremely; fucking

Possibly non-Sino-Vietnamese reading of Chinese 比 (SV: tỉ), short for tỉ-khâu-ni (比丘尼) < Pali bhikkhunī < Sanskrit भिक्षुणी (bhikṣuṇī).

If so, the correspondence between non-SV v- and SV t- is a manifestation of the chongniu phenomenon.

vãi • (娓, 尾, 𠉜, 𫱬)

1. middle-aged female pagoda-goer
2. Buddhist nun

• sãi