はいさい

Borrowed from Okinawan はいさい (haisai).

はいさい or ハイサイ • (haisai) 

1. (Okinawa, men's speech) hello

   Synonym: (women's speech) はいたい (haitai)

Likely related to Kikai 早さやー (へーさやー, hēsayā, “good morning”, literally “it's early”).

• IPA^(key): [haisai]

はいさい (haisai) 

1. (men's speech) hello, hi, hey, howdy (used by commoners in Naha)

   Synonyms: (women's speech) はいたい (haitai), (gender neutral) はい (hai)

   はいさい、御(ぐ)総(すー)様(よー)今日(ちゅー)拝(をぅが)なびら。

   Haisai, gusūyō chū wuganabira.

   Hello everyone, good day.

• “はいさい” in JLect - Japonic Languages and Dialects Database Dictionary, 2019.
• “ハイサイ（はいさい）” in Okinawan Dialect Dictionary - Ajima.
• “はいさい” in Okinawan Dictionary - KozaWeb.