Spongier refers to something that is soft, moist, and compressible, with a porous and springy texture. The antonyms for spongier are words that describe something that is firm, hard, dry, and compact. Some of the antonyms of spongier are dense, solid, rigid, tough, hard, unyielding, impenetrable, and compact. These words denote a texture that is resistant to pressure, firm to the touch, and lacking in porosity or springiness. While spongier is all about giving or absorbing pressure, the antonyms denote something that is unwavering and unyielding. Thus, knowing the antonyms of spongier can aid in expressing opposite meanings clearly in a sentence.