hair's breadth

CIDE DICTIONARY

hair's breadth,  

 The diameter or breadth of a hair; a very small distance; sometimes, definitely, the forty-eighth part of an inch.  [1913 Webster]
"Every one could sling stones at an hairbreadth and not miss."  [1913 Webster]

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hair's breadth

Nearness

N nearness, proximity, propinquity, vicinity, vicinage, neighborhood, adjacency, contiguity, short distance, short step, short cut, earshot, close quarters, stone's throw, bow shot, gun shot, pistol shot, hair's breadth, span, purlieus, neighborhood, vicinage, environs, alentours, suburbs, confines, banlieue, borderland, whereabouts, bystander, neighbor, borderer, approach, convergence, perihelion, near, nigh, close at hand, near at hand, close, neighboring, bordering upon, contiguous, adjacent, adjoining, proximate, proximal, at hand, handy, near the mark, near run, home, intimate, near, nigh, hard by, fast by, close to, close upon, hard upon, at the point of, next door to, within reach, within call, within hearing, within earshot, within an ace of, but a step, not far from, at no great distance, on the verge of, on the brink of, on the skirts of, in the environs, at one's door, at one's feet, at one's elbow, at one's finger's end, at one's side, on the tip of one's tongue, under one's nose, within a stone's throw, in sight of, in presence of, at close quarters, cheek by jole, cheek by jowl, beside, alongside, side by side, tete-a-tete, in juxtaposition, yardarm to yardarm, at the heels of, on the confines of, at the threshold, bordering upon, verging to, in the way, about, hereabouts, thereabouts, roughly, in round numbers, approximately, approximatively, as good as, well-nigh.

Thinness

N narrowness, thinness, narrowness, closeness, exility, exiguity, line, hair's breadth, finger's breadth, strip, streak, vein, monolayer, epitaxial deposition, thinness, tenuity, emaciation, macilency, marcor, shaving, slip, thread paper, skeleton, shadow, anatomy, spindleshanks, lantern jaws, mere skin and bone, middle constriction, stricture, neck, waist, isthmus, wasp, hourglass, ridge, ghaut, ghat, pass, ravine, narrowing, coarctation, angustation, tapering, contraction, narrow, close, slender, thin, fine, thread-like, finespun, gossamer, paper-thin, taper, slim, slight-made, scant, scanty, spare, delicate, incapacious, contracted, unexpanded &c (expand), slender as a thread, emaciated, lean, meager, gaunt, macilent, lank, lanky, weedy, skinny, scrawny slinky, starved, starveling, herring gutted, worn to a shadow, lean as a rake, thin as a lath, thin as a whipping post, thin as a wafer, hatchet-faced, lantern-jawed, attenuated, shriveled, extenuated, tabid, marcid, barebone, rawboned, monomolecular.