Un ample means insufficient or narrow, so antonyms for this term would be generous, sufficient, or spacious. Generous indicates that the object or space is abundant or liberal in size, quality, or amount. Similarly, sufficient indicates that it is enough, suitable, or satisfactory for a particular purpose. Lastly, spacious conveys that the object or space is ample or capacious, providing a vast area or enough room to move around freely. These terms are useful opposite terms for un ample, and they convey the opposite meaning by indicating that something is plentiful, satisfying, or vast.