Idiolect

An idiolect (sometimes misspelled: ideolect) is a variety of a language unique to an individual. It is manifested by patterns of word selection and grammar, or words, phrases or idioms that are unique to that individual. (That is, every individual has an idiolect; the grouping of words and phrases is unique, rather than individuals using specific words that nobody else uses.) An idiolect can easily evolve into an ecolect - a dialect variant specific to a household.