A person who attends or participates in a beanfeast; someone who goes to a celebration or party.
From beanfeast combined with the suffix -er (agent noun). This term emerged alongside 'beanfeast' in 19th-century British usage.
The existence of 'beanfeaster' shows how English automatically generates new words—once you have 'beanfeast,' you immediately need a word for 'someone who beanfeasts'!
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