1

ha

play
interjection \ˈhä\
variants: or

Definition of ha

  1. —used especially to express surprise, joy, or triumph

Examples of ha in a Sentence

  1. ha! I was right all along!

Origin and Etymology of ha

Middle English, from Old English


2

ha

abbreviation

Definition of ha

  1. hectare


HA

abbreviation

Definition of HA

  1. hour angle


HA Defined for English Language Learners

ha

play
interjection

Definition of ha for English Language Learners

  • —used especially to express surprise or a feeling of pleasure that you have when you do something or find out about something


HA Defined for Kids

ha

interjection \ˈhä\
variants: or

hah

\ˈhä\

Definition of ha for Students

  1. —used to show surprise or joy Ha! I knew you'd come.


Medical Dictionary

HA

abbreviation

Medical Definition of HA

  1. 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, 20 Oct. 2011



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to bring about or cause (something)

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