S: (n) self-feeder, feeder (a machine that automatically provides a supply of some material) "the feeder discharged feed into a trough for the livestock"
S: (n) device (an instrumentality invented for a particular purpose) "the device is small enough to wear on your wrist"; "a device intended to conserve water"
S: (n) feeder (an animal that feeds on a particular source of food) "a bark feeder"; "a mud feeder"