Inconceivable is a word that means impossible or unimaginable. Antonyms are words that are opposite in meaning to a given word. The antonyms for inconceivable include conceivable, possible, imaginable, likely, and probable. Conceivable means something that can be realized, understood, or imagined. Possible refers to something that can happen or exist. Imaginable is another word that suggests that something can be visualized or conceived in the mind. Likely means that something is more likely to happen or exist. Probable refers to something that is likely to happen or exist based on evidence or probability. These antonyms help to provide a range of meaning for the concept of something being possible to happen or exist.