sponge

sponge (http://definr.com/sponge)

     n 1: a porous mass of interlacing fibers the forms the internal
          skeleton of various marine animals and usable to absorb
          water or any porous rubber or cellulose product
          similarly used
     2: a follower who hangs around a host (without benefit to the
        host) in hope of gain or advantage [syn: leech, parasite,
         sponger]
     3: primitive multicellular marine animal whose porous body is
        supported by a fibrous skeletal framework; usually occurs
        in sessile colonies [syn: poriferan, parazoan]
     v 1: wipe with a sponge, so as to clean or moisten
     2: ask for and get free; be a parasite [syn: mooch, bum, cadge,
         grub]
     3: erase with a sponge; as of words on a blackboard
     4: soak up with a sponge
     5: gather sponges, in the ocean