composter UK /ˈkɒmpɒstə/US /kɑmˈpoʊstɚ/ noun2 •A person or business that composts wasteThe company, the major composter in this area, will soon have much more trash coming its way because Seattle is making food waste yet another mandatory recycling ingredient in its already long list. — 2007 •A container for producing compost.Ms. Fehrenbacher also liked the NatureMill, a small indoor composter made of recycled and recyclable polypropylene that converts food waste into fertilizer for houseplants and gardens. — 2009 formscomposters