not clearly or explicitly stated or expressed: vague promises.
indefinite or indistinct in nature or character, as ideas or feelings: a vague premonition of disaster.
not clear or distinct to the sight or any other sense; perceptible or recognizable only in an indefinite way: vague shapes in the dark; vague murmurs behind a door.
not definitely established, determined, confirmed, or known; uncertain: a vague rumor; The date of his birth is vague.
(of persons) not clear or definite in thought, understanding, or expression: vague about his motives; a vague person.