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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

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.

Ovitz, the former superagent, says he’ll always stop to say hi, but: “We all know: Don’t hang out.”

From The Wall Street Journal • Mar. 9, 2026

Get some rest, pal, and say hi to Susie for me.

From Slate • Nov. 24, 2025

If you go, don’t be shy, and say hi, as it’s the time of the year when I visit most often.

From Los Angeles Times • Nov. 19, 2025

"I like to say hi because people think actors are special. We're not at all," he smiles.

From BBC • Nov. 3, 2025

Ayesha gives me a halfhearted thumbs-up and then walks over to say hi to Nadia, who is already weeding next to Nadeem.

From "Internment" by Samira Ahmed

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.