ha

1 of 3

interjection

ˈhä 

variants or hah

—used especially to express surprise, joy, or triumph

ha

2 of 3

abbreviation (1)

hectare

HA

3 of 3

abbreviation (2)

1

hemagglutinin

Different circulating influenza A viruses are identified by referring to two signature proteins on their surfaces. One is hemagglutinin (HA), which has at least 15 known variants, or subtypes.

—Jeffery K. Taubenberger et al.

2

hour angle

Synonyms of ha

Interjection

• hey

Examples of ha in a Sentence

Interjection

ha! I was right all along!

Recent Examples on the Web

Interjection

Kim and his cast joined the festivities, with the film starring host Kim Min-ha alongside Joo Jong-hyuk, Han Sun-hwa, Chang Ryul, Shim Eun-kyung, Lee Hee-jun, Jeon So-young and Kim Dong-hwi. — Patrick Brzeski, HollywoodReporter, 6 Oct. 2026

This idea of art as an impermanent intervention in the situation of things seems to be the essence of Mono-ha in Japan. — Barry Schwabsky, Artforum, 1 Oct. 2026

His friend’s father ha died, leaving behind tens of thousands of vinyl records and CDs dating back to the 1920s. — Emma Hall, Sacbee.com, 30 Sep. 2026

Public safety officials said there was no evidence of foul play, and an autopsy ha been scheduled. — Adam Harrington, CBS News, 28 Sep. 2026

Word History

Etymology

Interjection

Middle English, from Old English

First Known Use

Interjection

before the 12th century, in the meaning defined above

Phrases Containing ha

• ha-ha
• hoo-ha

Rhymes for ha

• aah
• ah
• ahh
• aw
• awe
• bah
• blah
• bra
• caw
• claw
• craw
• daw

Kids Definition

ha

interjection

variants or hah

ˈhä

—used to express surprise, joy, or victory

Medical Definition

HA

abbreviation

hemagglutinin

Seasonal strains … evade our immune systems after vaccination or previous infection by constantly changing the structure of their hemagglutinin (HA) surface protein.

—Charles J. Russell, The New England Journal of Medicine