WordNet sense 1 (any of certain coarse weedy plants with long taproots, sometimes used as table greens or in folk medicine):

sorrel, sour grass

WordNet sense 2 (a platform built out from the shore into the water and supported by piles; provides access to ships and boats):

pier, wharf, wharfage

WordNet sense 3 (a platform where trucks or trains can be loaded or unloaded):

loading dock

WordNet sense 4 (landing in a harbor next to a pier where ships are loaded and unloaded or repaired; may have gates to let water in or out):

dockage, docking facility

WordNet sense 5 (a short or shortened tail of certain animals):

bob, bobtail

WordNet sense 6 (remove or shorten the tail of an animal):

tail