Vague
Part of speech: adjective
Definition: not clearly expressed; stated in indefinite terms. not having a precise meaning. not clearly defined, grasped, or understood; indistinct; slight. not clearly felt or sensed; somewhat subconscious. not thinking or expressing one's thoughts clearly or precisely. lacking expression; vacant. not sharply outlined; hazy.
Example sentence: No problem can be solved until it is reduced to some simple form. The changing of a vague difficulty into a specific, concrete form is a very essential element in thinking.
Unclear
Part of speech: adjective
Definition: Ambiguous; liable to more than one interpretation.Not clearly or explicitly defined.Not easy to see or read; indecipherable or unreadable.
Example sentence: Device makers, especially consumer-focused ones, have been the Achilles' heel of IoT security. These vendors have often viewed proper security implementations as extra cost, complexity, and time-to-market burdens with an unclear payoff.