[a. F. cube (14th c. in Littré) ad. late L. cubus, a. Gr. κύβος a cube, orig. a die for playing with.]
1. Geom. One of the five regular solids; a solid figure contained by six equal squares and eight rectangular solid angles; a regular hexahedron.
[1398. Trevisa, Barth. De P. R., XIX. cxxvii. (1495), 928. Suche a fygure is callyd Cubus.]
1551. Recorde, Cast. Knowl. (1556), 156 [see CUBICLY].
1570. Billingsley, Euclid, XI. def. xxi. 318. A Cube is a solide or bodely figure contayned vnder sixe equall squares.
1692. Bentley, Boyle Lect., ii. 58. Spheres, or Cubes, or Pyramids, or Cones.
1753. Hogarth, Anal. Beauty, 9. The most plain and regular forms, such as cubes and spheres.
1884. trans. Lotze’s Logic, 229. As the side of a cube increases, its volume must also continuously increase, without any alteration in its shape.
b. A material body of this form; a cubical block of anything, e.g., of tea, sugar.
1626. Bacon, Sylva, § 99. Take … a square Vessel of iron, in form of a Cube … put it into a Cube of Wood.
1863. Fawcett, Pol. Econ., III. v. 342. The Chinese use pressed cubes of tea.
2. Arith. and Alg. The product formed by multiplying any quantity into its square; the third power of a quantity.
1557. Recorde, Whetst., C iv. When I saie twoo tymes twoo, twise, maketh 8. that number is a sounde number: and is named a Cube.
1646. Sir T. Browne, Pseud. Ep., IV. xii. 219. By perfect and sphericall numbers, by the square and cube of 7 and 9 and 12.
a. 1721. Keill, Maupertuis’ Diss. (1734), 21. The periodical Times of the several Planets, are in proportion to the square Roots of the Cubes of their distances from the Sun.
1838. De Morgan, Ess. Probab., 63. The sum of all the squares of numbers is nearly one third of the cube of the last number.
3. attrib. (= CUBIC a. 2), and in Comb., as cube foot; † cube-bone = CUBOID bone; cube-number, one that is the cube of an integer; cube-ore, a name for PHARMACOSIDERITE; cube powder, gunpowder made in large cubical grains; cube root, that number of which the given number is the cube; cube-spar, a name for ANHYDRITE.
1570. Billingsley, Euclid, VII. def. xx. 187. A cube number is … that which is contayned vnder three equall numbers.
1615. Crooke, Body of Man, 1007. The heele is articulated into a sinus of the Cube-bone.
1696. Phillips, Cube Root.
1751. Halfpenny, Designs Chinese Bridges, II. 8. 1040 Cube Feet of Timber.
1804. R. Jameson, Char. Min., I. 571. Cube Spar. Ibid., II. 345. Cube-Ore.
1827. Hutton, Course Math., I. 8. ∛5, or 51/3, denotes the cube root of the number 5.
b. Sometimes used after a measure expressing the length of the edge of a cube; e.g., 6 feet cube = of cubical form, and measuring 6 ft. in each direction, i.e., containing 6 × 6 × 6 or 216 cubic feet.
1707. S. Clarke, Third Defence (1712), 13. The Magnitude of a foot cube of Matter … is made up of Inches cube.
1776. G. Semple, Building in Water, 94. If the Pit was a Mile Cube.
1849. Dana, Geol., ii. (1850), 74. Some of these [masses of coral] were six feet cube.
