From Proto-Tai *piːᴬ (“year”). Cognate with Northern Thai ᨸᩦ, Lao ປີ (pī), Lü ᦔᦲ (ṗii), Shan ပီ (pǐi), Thai ปี (bpii), Ahom 𑜆𑜣 (pī), Zhuang bi, Bouyei bil.
ᥙᥤ (pi) (1963 orthography ᥙᥤ)