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 paH) (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

vãi • (娓, 尾, 𠉜, 𫱬)

1. middle-aged female pagoda-goer
2. Buddhist nun
   • 16th century, Nguyễn Thế Nghi's (attributed) Tân biên Truyền kỳ mạn lục tăng bổ giải âm tập chú (新編傳奇漫錄增補解音集註), giải âm/translation of “The Tale of the Abandoned Pagoda in Đông Triều” in Truyền kỳ mạn lục ("Casual Record of Transmitted Strange-Tales") by Nguyễn Dữ.

     仕娓𨪷𩯀共民平㐌姅

     Sãi vãi gọt tóc cùng dân bình đã nửa.

     Those who cut their hair and became Buddhist monks and Buddhist nuns constituted half of the common populace.

   • Nam quốc phương ngôn tục ngữ bị lục (南國方言俗語備錄 "Records of the Southern Nation's regional adages and common sayings"), 1914 version, 11b

     師呐師沛娓呐娓咍 ― Sư nói sư phải; vãi nói vãi hay. ― The Buddhist monk says he is right; the Buddist nun says she is knowledgeable.

• sãi