Definition of "drainer"

drainer¹

noun
plural drainers
1. That which drains.
  Quotations
  The radical shift in mentality is even more necessary when analysts see Education simply as a drainer of resources.
  1999, Pai Obanya, The dilemma of education in Africa, page 175
  I know that poor form is one of the biggest drainers of energy, so even though I slowed down significantly I made a very conscious effort to maintain good form.
  2003, Gail Waesche Kislevitz, The Spirit of the Marathon, page 78
2. A frame or rack for allowing washed crockery etc to dry naturally.
3. A perforated rack on which washed dishes, etc. may be placed in order to dry.
4. (fandom slang) Alternative form of Drainer

drainer²

noun
plural drainers
1. A person who explores drains, tunnels, or sewers.
2. Alternative spelling of Drainer