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Synonyms

hi

1 American  
[hahy] / haɪ /

interjection

  1. (used as an exclamation of greeting) hello!


hi 2 American  
[hahy] / haɪ /

adjective

  1. an informal, simplified spelling of high.

    hi fidelity.


HI 3 American  

abbreviation

  1. Hawaii (approved especially for use with zip code).

  2. Meteorology. heat index. Also H.I.


H.I. 4 American  

abbreviation

  1. Hawaiian Islands.

  2. Meteorology. heat index. Also HI


HI 1 British  

abbreviation

  1. Hawaii (state)

  2. Hawaiian Islands

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

hi 2 British  
/ haɪ /
  1. an informal word for hello

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

hi 3 British  
/ haɪ /

interjection

  1. an expression used to attract attention

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of hi

First recorded in 1425–75; late Middle English hy, perhaps variant of hei hey

Explanation

Hi is a common greeting, more casual than "hello." When you walk down the street in a small town, it might seem like everyone you pass says "hi." The word hi is a good, nearly all-purpose greeting — it's appropriate in all but the most formal circumstances, so you might want to skip saying, "Hi" to the Queen when you meet her. When you greet someone, you have a lot of words to choose from, including "hey," "hello," "hiya," and "howdy," but hi is probably the most common. The first mention of hi attributes it to a Kansas native American in the 1800s.

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Vocabulary lists containing hi

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

She stops to talk, or shouts a cheery "Hi, you alright?" to nearly everybody passing on foot or by car.

From BBC • Jun. 4, 2026

Viv Chen: Hi, Tory, it’s a pleasure to meet.

From Los Angeles Times • May 14, 2026

The Hi Desert Lo-Fi Lit Fest is hosting free panels, workshops, and readings all weekend along.

From Los Angeles Times • Mar. 19, 2026

On 12 November, Mandelson received an email with the subject "Paris" which read: "Hi peter, Valdson, Jeffrey's driver, will be picking you up today from the train station... see you this evening!"

From BBC • Feb. 4, 2026

"Hi, Mr. McGuire," the class replied in unison.

From "The Cinderella Ballet Mystery: Nancy Drew and the Clue Crew, #4" by Carolyn Keene

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