IQuit iCarly - S3-E8
Continuity mistake: Carly, Sam, Fleck and Dave are sitting at one table at the Groovy Smoothy sipping a new smoothy flavor with T-Bo standing next to them. Suddenly the smoothy gets too spicy so all four go to another table and gulp down other people's waters then sit back down. The waiter places two glasses in front of Dave and Fleck. The waiter starts to pass behind T-Bo with 2 more glasses of water, but the shot immediately cuts to Sam and Carly drinking water.
Answer: In direction translation it means 'Mischievous Spirit'. 'Hob' as in HobGoblin means clown or prankster, and 'Knocker' was an old age term for Poltergeists in mines. Miners would often complain of hearing knocking sounds down mines when there was no-one else down there, hence 'Knocker'. It's not a regular English expression though.
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