It depends on who you ask. Generally to be considered a dialect, it has to be mutually intelligible with the parent language. If it’s not then it’s a language of its own.
If you’re deferring to another language to answer grammatical or syntactic questions about it, then it’s a dialect of that language.
But there is no universally accepted definition or set of criteria for determining a dialect vs language, just what’s most commonly agreed upon.
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