The present participle of broom, meaning to sweep with a broom or to clear away like a broom sweeps.
From broom (verb) + -ing (present participle suffix). The verb 'broom' comes from the noun, following a pattern where tools become verbs describing their use.
The -ing form of broom shows how verbs can come from nouns in English—if you have a tool called a broom, it's natural to create a verb meaning 'to use a broom,' and this pattern gave us dozens of everyday verbs.
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