castings
n.pl.— «The worm’s waste materials, delicately referred to as “castings,” or, indelicately, as “poop,” are eaten by microbes and fungi, allowing them to grow and reproduce and sequester minerals from the soil.» —“Vessels of the Holy Spirit or Agents of Entropy?” by ArchaicFuturist Young Anabaptist Radicals May 11, 2007. (source: Double-Tongued Dictionary)