Taitie is slang for potatoe. Although often refered to when talking about food (e.g. Jacket Taitie for Jacket potatoe) it can also be used as a friendly form of telling someone they are a bit daft (e.g. dont be a taitie).
As far as I know this is slang in the North-east area of England.
"Jesus, Tara is a right taitie!"
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