1. A porous mass of interlacing fibers that forms the internal skeleton of various marine animals and usable to absorb water or any porous rubber or cellulose product similarly used Noun
2. Someone able to acquire new knowledge and skills rapidly and easily Noun
3. A follower who hangs around a host (without benefit to the host) in hope of gain or advantage Noun
4. Primitive multicellular marine animal whose porous body is supported by a fibrous skeletal framework; usually occurs in sessile colonies Noun
5. Wipe with a sponge, so as to clean or moisten Verb
6. Ask for and get free; be a parasite Verb
7. Erase with a sponge; as of words on a blackboard Verb