Learn how to say Spongiest correctly in English with this tutorial pronunciation video.
Oxford dictionary definition of the word spongy:
adjective (spongier, spongiest)
like a sponge, especially in being porous, compressible, or absorbent:
a soft, spongy blanket of moss
(of metal) having an open, porous structure:
(chiefly of a motor vehicle’s braking system) lacking firmness.