slider \slid"er\, n.
   1. one who, or that which, slides; especially, a sliding part
      of an instrument or machine.
      1913 webster

   2. zool. the red-bellied terrapin pseudemys rugosa.
      local, u. s. 
      1913 webster

   3. zool. any of several north american freshwater turtles
      of the genus chrysemis; some, such as chrysemis
      scripta are sold commercially as pets. --rhud
      pjc

   4. baseball a fast pitch that breaks slightly just in front
      of the batter, in the same direction as a curve ball i.
      e., away from the side from which it was thrown.
      pjc

   slider pump, a form of rotary pump.
      1913 webster
see also:
pseudemys rugosa chrysemis chrysemis scripta slider pump