One who golls, or in dialect, a person or animal with a distinctive gall or boldness; could also refer to something that rolls or moves.
From gall or goll plus the agent suffix -er, indicating someone who performs an action. English agent nouns using -er are productive even with rare base words.
The -er suffix is one of English's most creative tools—you can almost always add it to a verb and make a 'doer,' which means speakers are constantly inventing new occupational words like 'goller' even for uncommon activities.
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