The American definition:

1.) An excitable, hyper, or jittery person.

2.) To act in a wild manner.

As defined by white disabled activists from the UK on twitter:

1.) An ableist slur short for "spastic" or "spasticity"; which directly refers to Spastic Diplegia, and anyone (preferably those with power and followers) who uses the term in any context outside of medical science must apologize and be ashamed for having used it.
United States: This kid I'm babysitting is such a spaz. He gets one piece of candy in him and he's bouncing off the walls.

United Kingdom: Even though we call "fags" cigarettes in the UK (and no one has cancelled all of Britain yet), when Beyonce and Lizzo used the word "spaz" in a jovial context, we fought on social media to bring worldwide attention to the NEGATIVE connotation.

Also UK: "Spaz" has historically been a part of African American English Vernacular, but any disabled people of color from the US disagreeing with us will be a.) ignored in the conversation on Twitter, or B.) be accused of "reverse racism".
by UnknownCryptid January 19, 2023
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A word used to describe someone that is hyper. It is usually directed at someone who is attention deficit or sped.
"sit down spaz"

-The Benchwarmers
by Bezznzz April 12, 2023
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a person who behaves like a retard, know one really knows how to use this word properly
by __jesuschrist January 27, 2019
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Person 1- Ava is a spaz
Ava- what is a spaz?
Person 1- a crackhead
by tfuyguhiuiooihiu November 20, 2019
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someone who has so much energy they freak out and they have a panic attack.
ellie was being a spaz about her exam
by 1paradox January 8, 2016
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