sinker

Short definition from Wiktionary

Noun

1. 1
   That which sinks or descends.
2. 2
   One who sinks something.
3. 3
   A weight used in fishing to cause the line or net to sink.
4. 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. 5
   A sinker nail, used for framing in current construction.
6. 6
   A doughnut; a biscuit.
7. 7
   In knitting machines, one of the thin plates, blades, or other devices, that depress the loops upon or between the needles.