dock (n.1)

"ship's berth, any structure in or upon which a ship may be held for loading, repairing, etc.," late 15c., dokke, from Middle Dutch or Middle Low German docke, which is perhaps ultimately (via Late Latin *ductia "aqueduct") from Latin ducere "to lead" (from PIE root *deuk- "to lead"); or possibly from a Scandinavian word for "low ground" (compare Norwegian dokk "hollow, low ground"). The original sense was perhaps "furrow a grounded vessel makes in a mud bank."

"where accused stands in court," 1580s, probably originally rogue's slang, from Flemish dok "pen or cage for animals," which is of unknown origin.

"cut off or clip an animal's tail," late 14c., from dok (n.) "fleshy part of an animal's tail" (mid-14c.), which is from Old English -docca "muscle" or an Old Norse equivalent, from Proto-Germanic *dokko "something round, bundle" (source also of Old Norse dokka "bundle; girl," Danish dukke "a bundle, bunch, ball of twine, straw, etc.," also "doll," German Docke "small column, bundle; doll, smart girl").

The general meaning "deduct a part from," especially "to reduce (someone's) pay for some infraction" is recorded by 1815. Related: Docked; docking.

name for various tall, coarse weeds or herbs, Old English docce, from Proto-Germanic *dokkon (source also of Middle Dutch docke-, German Docken-, Old Danish dokka), akin to Middle High German tocke "bundle, tuft," and ultimately to the noun source of dock (v.1).

 "to bring or place (a ship) into a dock," 1510s, from dock (n.1). Intransitive sense of "to come into a dock" is by 1892. Of spaceships, by 1951. Related: Docked; docking.