Cusp

• POS: Noun

CIDE DICTIONARY

Cusp, n. [L. cuspis, -idis, point, pointed end.].

•  A triangular protection from the intrados of an arch, or from an inner curve of tracery.  [1913 Webster]
•  The beginning or first entrance of any house in the calculations of nativities, etc.  [1913 Webster]
•  The point or horn of the crescent moon or other crescent-shaped luminary.  [1913 Webster]
•  A multiple point of a curve at which two or more branches of the curve have a common tangent.  [1913 Webster]
•  A prominence or point, especially on the crown of a tooth.  [1913 Webster]
•  A sharp and rigid point.  [1913 Webster]

Cusp, v. t. 

 To furnish with a cusp or cusps.  [1913 Webster]

OXFORD DICTIONARY

Cusp, n.
1 an apex or peak.
2 the horn of a crescent moon etc.
3 Astrol. the initial point of a house.
4 Archit. a projecting point between small arcs in Gothic tracery.
5 Geom. the point at which two arcs meet from the same direction terminating with a common tangent.
6 Bot. a pointed end, esp. of a leaf.
7 a cone-shaped prominence on the surface of a tooth esp. a molar or premolar.
8 a pocket or fold in a valve of the heart.

Derivative

cuspate adj. cusped adj. cuspidal adj.

Etymology

L cuspis, -idis point, apex

ROGET THESAURUS

Cusp

Angularity

N angularity, angularness, aduncity, angle, cusp, bend, fold, notch, fork, bifurcation, elbow, knee, knuckle, ankle, groin, crotch, crutch, crane, fluke, scythe, sickle, zigzag, kimbo, akimbo, corner, nook, recess, niche, oriel, coign, right angle, obliquity, angle of 45 degrees, miter, acute angle, obtuse angle, salient angle, reentering angle, spherical angle, angular measurement, angular elevation, angular distance, angular velocity, trigonometry, goniometry, altimetry, clinometer, graphometer, goniometer, theodolite, sextant, quadrant, dichotomy, triangle, trigon, wedge, rectangle, square, lozenge, diamond, rhomb, rhombus, quadrangle, quadrilateral, parallelogram, quadrature, polygon, pentagon, hexagon, heptagon, octagon, oxygon, decagon, pyramid, cone, Platonic bodies, cube, rhomboid, tetrahedron, pentahedron, hexahedron, octahedron, dodecahedron, icosahedron, eicosahedron, prism, pyramid, parallelopiped, curb roof, gambrel roof, mansard roof, angular, bent, crooked, aduncous, uncinated, aquiline, jagged, serrated, falciform, falcated, furcated, forked, bifurcate, zigzag, furcular, hooked, dovetailed, knock kneed, crinkled, akimbo, kimbo, geniculated, oblique, fusiform, wedge-shaped, cuneiform, cuneate, multangular, oxygonal, triangular, trigonal, trilateral, quadrangular, quadrilateral, foursquare, rectangular, square, multilateral, polygonal, cubical, rhomboid, rhomboidal, pyramidal.

Sharpness

N sharpness, acuity, acumination, spinosity, point, spike, spine, spicule, spiculum, needle, hypodermic needle, tack, nail, pin, prick, prickle, spur, rowel, barb, spit, cusp, horn, antler, snag, tag thorn, bristle, Adam's needle, bear grass, tine, yucca, nib, tooth, tusk, spoke, cog, ratchet, crag, crest, arete, cone peak, sugar loaf, pike, aiguille, spire, pyramid, steeple, beard, chevaux de frise, porcupine, hedgehog, brier, bramble, thistle, comb, awn, beggar's lice, bur, burr, catchweed, cleavers, clivers, goose, grass, hairif, hariff, flax comb, hackle, hatchel, heckle, wedge, knife edge, cutting edge, blade, edge tool, cutlery, knife, penknife, whittle, razor, razor blade, safety razor, straight razor, electric razor, scalpel, bistoury, lancet, plowshare, coulter, colter, hatchet, ax, pickax, mattock, pick, adze, gill, billhook, cleaver, cutter, scythe, sickle, scissors, shears, pruning shears, cutters, wire cutters, nail clipper, paper cutter, sword, bodkin, belduque, bowie knife, paring knife, bushwhacker, drawing knife, drawing shave, microtome, chisel, screwdriver blade, flint blade, guillotine, sharpener, hone, strop, grindstone, whetstone, novaculite, steel, emery, sharp, keen, acute, acicular, aciform, aculeated, acuminated, pointed, tapering, conical, pyramidal, mucronate, mucronated, spindle shaped, needle shaped, spiked, spiky, ensiform, peaked, salient, cusped, cuspidate, cuspidated, cornute, cornuted, cornicultate, prickly, spiny, spinous, spicular, thorny, bristling, muricated, pectinated, studded, thistly, briary, craggy, snaggy, digitated, two-edged, fusiform, dentiform, denticulated, toothed, odontoid, starlike, stellated, stelliform, sagittate, sagittiform, arrowheaded, arrowy, barbed, spurred, acinaciform, apiculate, apiculated, aristate, awned, awny, bearded, calamiform, cone-shaped, coniform, crestate, echinate, gladiate, lanceolate, lanciform, awl, awl-shaped, lance-shaped, awl- shaped, scimitar-shaped, sword-shaped, setarious, spinuliferous, subulate, tetrahedral, xiphoid, cutting, sharp edged, knife edged, sharp as a razor, keen as a razor, sharp as a needle, sharp as a tack, sharpened, set.