We've found 4 phrases for vague (0.174 seconds):

fine line »    A difference, albeit vague and difficult to discern.

hand waving »    Discussion or argumentation involving approximation, vagueness, educated guessing, or the attempt to explain or excuse vagaries.

out of sorts »    Irritable or somewhat unwell, with vague medical symptoms.

ring a bell »    To seem at least vaguely familiar.

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