The people who think clarity involves lack of ambiguity, so we have to strive to eliminate all multiple meanings and should never let a word develop a new sense… they simply don't get it about how language works, do they?
Languages love multiple meanings. They lust after them. They roll around in them like a dog in fresh grass.
The other day, as I reading a discussion in our comments about whether English draftable does or doesn't refer to the same concept as Finnish asevelvollisuus ("obligation to serve in the military"), I happened to be sitting in a current of uncomfortably cold air. So of course I wondered how the English word draft came to refer to military conscription as well as air flow. And a few seconds of thought brought to mind several others senses of the the noun draft and its associated verb. I figured that this must represent a confusion of several originally separate words. But then I looked it up.
The OED explains that the origin of all of these various senses is a "verbal abstract from Common Germanic dragan to draw"; and its list of glosses — merely for the noun form — is an impressive one. (Senses flagged as obsolete or archaic are presented in acqua.)
"The action, or an act, of drawing or pulling, esp. of a vehicle, plough, etc."; "Drawing of breath"; "Drawing motion or action"; "That which is drawn", "A load", "A quantity drawn: used as a specific measure of something drawn, extracted, or taken up"; "A drawbridge"; "Something used in drawing or pulling, as harness for horses to draw with"; "A team of horses or other beasts of draught, together with that which they draw"; "Drawing, attraction; tendency, inclination, impulse"; "The act of drawing a net for fish, or for birds"; "A place where a net is wont to be drawn"; "The quantity of fish taken in one drawing of the net; a take"; "A measure of weight of eels, equal to 20 lbs"; "The drawing of a bow; a bowshot; also, the distance which a bow can shoot"; "The drawing or sweep of a weapon; a stroke, a blow"; "The drawing of a saw through a block of wood or stone; hence a measure of sawyers' work"; "The drawing of liquid into the mouth or down the throat; an act of drinking, a drink; the quantity of drink swallowed at one ‘pull’"; "A fanciful name for a ‘company’ of butlers"; "A dose of liquid medicine; a potion"; "Drawing of smoke or vapour into the mouth, inhaling; that which is inhaled at one breath"; "The ‘drinking in’ of something by the mind or soul; a portion of something, pleasurable or painful, ‘drunk’, partaken of, or experienced"; "The action of drawing out to a greater length, extension, stretching; concr. that which is drawn out or spun, a thread. spec. in Cotton-spinning, etc. the ‘drawing’ or elongation of the slivers by passing them between pairs of rollers revolving at different speeds"; "The action of ‘drawing’ or displacing (so much) water; the depth of water which a vessel draws, or requires to float her"; "The action of moving along course, going, way"; "Course, way of going on"; "A ‘move’ at chess or any similar game"; "pl. A game played by two persons on a board of the same kind as that used in chess, which game it somewhat resembles, though of much simpler character, all the pieces or ‘men’ being of equal value and moving alike diagonally. (In U.S. called checkers, in Scotl. dambrod.)"; "One of the pieces used in this game"; "A current, stream, flow"; "A stream course, a ravine"; "Hydraulics. The area of an opening for a flow of water"; "A current of air, esp. in a confined space, as a room or a chimney"; "An appliance for creating a draught in a fire-place; a blower"; "The drawing of a brush, pen, pencil, or the like, across a surface, so as to make a line or mark; the mark so made; a stroke"; "Drawing of figures; delineation"; "That which is drawn or delineated; a representation (of an object) by lines drawn on the surface of paper, etc.; a drawing, picture, sketch"; "Representation in sculpture; a sculptured figure"; "An outline, sketch, or design, preparatory to a completed work of art"; "Image, representation; something devised or designed like a work of art; slight or preliminary sketch or outline"; "A sketch in words; a slight or concise account, ‘outline’, abstract"; "A plan, map, chart, plot"; "A ‘plan’ of something to be constructed, as a building"; "A pattern, an outline drawing"; "A preliminary ‘sketch’ or outline of a writing or document, from which the fair or finished copy is made"; "Something drawn up or devised; a scheme, plan, design, device; a plot; an artifice"; "The withdrawing, detachment, or selection of certain persons, animals, or things from a larger body for some special duty or purpose; the party so drawn off or selected; spec. in military use"; "The ‘drawing’ or withdrawing of money from a stock by means of an order written in due form"; "A formal written order for the payment of money, ‘drawn on’, or addressed to, a person holding funds available for this purpose"; "The act of drawing forth or out; drawing (as of lots)"; "Extraction, derivation; something derived, an emanation"; "A passage of a writing; an extract"; "An extract obtained by distillation"; "The action of drawing liquor from a vessel; the condition of being ready to be so drawn"; "Cookery. The entrails of an animal drawn out"; "A mild blister or poultice that ‘draws’"; "a part of the surface of the stone, hewn to the breadth of the chisel on the margin of the stone according to the curved or straight line to which the surface is to be brought"; "The bevel given to the pattern for a casting, in order that it may be drawn from the sand without injury to the mold"; "Weaving. The succession in which the threads of the warp are inserted into the heddles of the loom in order to produce the required pattern; the plan of ‘drawing’ of a warp"; "A cesspool, sink, or sewer".
(There is also some discussion, which I skip, of the complex history of the variable usage of the spellings "draught" and "draft". Note also that the denominal verb to draft is different from the verb to draw that draft derives from historically.)
The list of senses in the American Heritage Dictionary is slightly less elaborated, but still impressive. (Here all parts of speech are given, verbal and adjective senses as well as nominal ones.)
n. A current of air in an enclosed area.
n. A device that regulates the flow or circulation of air.
n. The act of pulling loads; traction.
n. Something that is pulled or drawn; a load.
n. A team of animals used to pull loads.
n. Nautical The depth of a vessel's keel below the water line, especially when loaded: a river vessel of shallow draft.
n. A heavy demand on resources.
n. A written order directing the payment of money from an account or fund.
n. A gulp, swallow, or inhalation.
n. The amount taken in by a single act of drinking or inhaling.
n. A measured portion; a dose.
n. The drawing of a liquid, as from a cask or keg.
n. An amount drawn: ordered two drafts of ale.
n. The process or method of selecting one or more individuals from a group, as for a service or duty: a candidate who did not pursue the nomination, but accepted a draft by the party convention.
n. Compulsory enrollment in the armed forces; conscription.
n. A body of people selected or conscripted.
n. Sports A system in which the exclusive rights to new players are distributed among professional teams.
n. The act of drawing in a fishnet.
n. The quantity of fish caught.
n. Any of various stages in the development of a plan, document, or picture: a preliminary draft of a report; the final draft of a paper.
n. A representation of something to be constructed.
n. A narrow line chiseled on a stone to guide a stonecutter in leveling its surface.
n. A slight taper given a die to facilitate the removal of a casting.
n. An allowance made for loss in weight of merchandise.
v. To select from a group for some usually compulsory service: drafted into the army.
v. To select from a group for placement on a sports team.
v. To draw up a preliminary version of or plan for.
v. To create by thinking and writing; compose: draft a speech.
v. To work as a drafter.
v. To move, ride, or drive close behind a fast-moving object so as to take advantage of the slipstream, especially in a race.
adj. Suited for or used for drawing heavy loads: oxen and other draft animals.
adj. Drawn from a cask or tap: draft beer.
idiom. on draft Drawn from a large container, such as a keg.
This amply illustrates Geoff's general point. But his simile, relating languages reveling in ambiguity to dogs rolling in new-mown grass, is slightly off target. What dogs are fond of rolling in, I believe, is anything that smells strongly, especially things like feces and carrion. Tom Davis, Why Dogs Do That (1998) offers two explanations, which subvert Geoff's simile in two different ways:
There are couple of theories, by no means mutually exclusive, that explain why dogs take such obvious and unabashed delight in rolling in stuff that makes us gag: excrement, carrion (the older and fouler, the better), anything and everything that is rotten, putrid and deliquescent. And they don't just roll in it; wriggling joyfully on their backs, they do their damnedest to smear it around and rub it in. The specific hypothesis suggest that dogs roll in stinky stuff to mask their own scent, and thus gain an edge over prey species […] (Contemporary human deer hunters do much the same thing when dousing their clothing with various bottled scents.)
The other theory, more general in application, holds that it's a way for a dog to tell other dogs where they've been and what they found there. A dog streaked with excrescence is viewed by his brethren as a storyteller, and canine society hold storytellers in high esteem.
On the first explanation, polysemy is a sort of ruse that allows us to sneak up on wary concepts. On the second one, humans who love to explore etymology are like dogs avidly smelling the crap that other dogs have rubbed into their fur.
Maybe that new-mown grass, even if semantically sanitized, was a better choice after all.