-interjection
Hai is a colloquialism used mainly in north western parts of Ireland especially in counties Monaghan, Cavan, Roscommon, Mayo and Galway.

An Irish cult TV show, Hardy Bucks, has served to spread the use of this once localized colloquialism throughout most of the country of Ireland and in small pockets of London, Germany, Holland and the Middle East. ‘Hai’ is actually the word 'Hey' and is used as an exclamation to call attention or to express pleasure, surprise, bewilderment, etc. However, due to the nature of the western Irish accent, the listener interprets the spelling as ‘Hai’.

The word is usually used as the final word of a sentence. It can be used in almost every context and situation but is most effective when used to conclude a question.
Stephen: "Are we going drinking Brandy Hai?"
Neil: "Does the Pope make the world a safer place for paedophiles hai?"
...
Brendan: "Come ere Hai"..(Expressing a need to draw attention to a subject matter), "I hope ye all have your Christmas jumpers for the 23rd Hai”(Here the word is used as an exclamation of intent).
by Kevin Prince Burgertang December 14, 2010
After Peter entered, Kijuna greeted him with a friendly hai.
by Kijuna January 17, 2004
A super cool Vietnamese name that anyone would really wish to have because it's pronounced "hi".
by pokemonkey January 7, 2010
'Yes' in Japanese, also a textual sigh used in some places, especially in Singapore.

Also, Haiz and Haix. (Freaky variations by adding X and Z's)
- Japanese -
Dad: Get off your computer and do your homework.

Son: Hai!

- Sighing -
Dad: Get off your computer and do your homework!

Daughter: *Hai*..
by One Urban Muffin February 15, 2004
Japanese for "yes." Can also mean "okay" or used to answer a roll call.
Teacher: Smith!
Smith: Hai!
by Sita Snape May 3, 2003