1. A seemingly contradictory statement that may nonetheless be true: the paradox that standing is more tiring than walking.
2. One exhibiting inexplicable or contradictory aspects: "The silence of midnight, to speak truly, though apparently a paradox, rung in my ears" (Mary Shelley).
3. An assertion that is essentially self-contradictory, though based on a valid deduction from acceptable premises.
4. A statement contrary to received opinion.