knot

noun

1.
a tight cluster of people or things
2.
any of various fastenings formed by looping and tying a rope (or cord) upon itself or to another rope or to another object
Derived from:
knot knotty
3.
a hard cross-grained round piece of wood in a board where a branch emerged
4.
(of ships and wind) a unit of speed equal to one nautical mile per hour or about 1.15 statute miles per hour
5.
something twisted and tight and swollen
Derived from:
knot knotty
6.
soft lump or unevenness in a yarn; either an imperfection or created by design
7.
a sandpiper that breeds in the Arctic and winters in the Southern Hemisphere