sinker Meaning, Definition & Usage

  1. noun a small ring-shaped friedcake
    donut; doughnut.
  2. noun a weight that sinks (as to hold nets or fishing lines under water)
  3. noun a pitch that curves downward rapidly as it approaches the plate

WordNet

Sink"er noun
Definitions
  1. One who, or that which, sinks. Specifically: (a) A weight on something, as on a fish line, to sink it. (b) In knitting machines, one of the thin plates, blades, or other devices, that depress the loops upon or between the needles.

Webster 1913