sinker

noun

1. That which sinks or descends.
2. One who sinks something.
3. A weight used in fishing to cause the line or net to sink.
4. Any of several high speed pitches that have a downward motion near the plate; a two-seam fastball, a split-finger fastball, or a forkball.
5. A sinker nail, used for framing in current construction.
6. A doughnut; a biscuit.
7. In knitting machines, one of the thin plates, blades, or other devices, that depress the loops upon or between the needles.