A growling sound made to express anger, annoyance, or playful aggression.
Onomatopoeia originating in English, directly imitating the sound a dog or angry person makes. The word is purely imitative with no etymological root in other languages.
Interestingly, this written representation of a growl actually shows how English speakers try to capture animal sounds differently than other languages—Spanish speakers might write 'grrr' slightly differently because the letter 'r' rolls in their language.
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