late Old English hæfen "haven, port," from Old Norse höfn "haven, harbor" or directly from Proto-Germanic *hafno- (source also of Danish havn, Middle Low German havene, German Hafen), perhaps from PIE root *kap- "to grasp" (source of have) on notion of place that "holds" ships. But it might rather be related to Old Norse haf, Old English hæf "sea" (see haff). Figurative sense of "refuge," now practically the only sense, is c. 1200.
common name of a type of trees noted for majestic height and the wide-spreading and gracefully curving branches, Old English elm, from Proto-Germanic *elmaz (source also of Danish elm, Old Norse almr, Old High German elme), perhaps from PIE root *el- (2) "red, brown" (see elk); cognate with Latin ulmus, Old Irish lem. German Ulme, Dutch olm are from or influenced by the Latin word. The toughest native European wood, used for ship-building, wheel-naves, etc. Middle English had adjective forms elmen, elmin, which survived longer in poetry. New Haven was informally the Elm City (1871).
Old English cniht "boy, youth; servant, attendant," a word common to the nearby Germanic languages (Old Frisian kniucht, Dutch knecht, Middle High German kneht "boy, youth, lad," German Knecht "servant, bondman, vassal"), of unknown origin. For pronunciation, see kn-. The plural in Middle English sometimes was knighten.
Meaning "military follower of a king or other superior" is from c. 1100. It began to be used in a specific military sense in the Hundred Years War, and gradually rose in importance until it became a rank in the nobility from 16c. Hence in modern British use, a social privilege or honorary dignity conferred by a sovereign as a reward, without regard for birth or deeds at arms. In 17c.-19c. a common jocularism was to call a craftsman or tradesman a knight of the and name some object associated with his work; e.g. knight of the brush for "painter." Knight in shining armor in the figurative sense is from 1917, from the man who rescues the damsel in distress in romantic dramas (perhaps especially "Lohengrin"). For knight-errant, see errant.
The horse-headed chess piece so called from mid-15c. Knights of Columbus, society of Catholic men, founded 1882 in New Haven, Connecticut, U.S.; Knights of Labor, trade union association, founded in Philadelphia, 1869; Knights of Pythias, secret order, founded in Washington, 1864.
"a bay, cove, inlet, or recess of a large body of water where vessels can load and unload and find shelter from storms; a harbor, whether natural or artificial," Old English port "a port, harbor, a place where there is a constant resort of vessels for the purpose of loading and unloading;" also "a town, market town, city," reinforced by Old French port "harbor, port; mountain pass." The Old English and Old French words both are from Latin portus "a port, harbor," figuratively "haven, place of refuge, asylum" (in Old Latin also "a house;" in Late Latin also "a warehouse"), originally "an entrance, a passage," akin to porta "a city gate, a gate, a door" (from PIE *prtu- "a going, a passage," suffixed form of root *per- (2) "to lead, pass over").
[I]in law, a place where persons and merchandise are allowed to pass into and out of the realm and at which customs officers are stationed for the purpose of inspecting or appraising imported goods. In this sense a port may exist on the frontier, where the foreign communication is by land. [Century Dictionary]
The figurative sense "place, position, or condition of refuge" is attested in English from early 15c.; phrase any port in a storm, indicating "any refuge is welcomed in adversity," is by 1749. A port of call (1810) is one paid a scheduled visit by a vessel in the course of its voyage. The verb meaning "to carry or bring into a port" is by 1610s.