The density of a substance relative to the density of water.

Roget 319: gravity, gravitation; weight; heaviness etc. adj.; specific gravity; pondorosity^†, pressure, load; burden, burthen^†; ballast, counterpoise; lump of, mass of, weight of.    lead, millstone, mountain, Ossa on Pelion.    weighing, ponderation^†, trutination^†; weights; avoirdupois weight, troy weight, apothecaries' weight; grain, scruple, drachma^†, ounce, pound, lb, arroba^†, load, stone, hundredweight, cwt, ton, long ton, metric ton, quintal, carat, pennyweight, tod^†.    [metric weights] gram, centigram, milligram, microgram, kilogram; nanogram, picogram, femtogram, attogram.    [Weighing Instrument] balance, scale, scales, steelyard, beam, weighbridge^†; spring balance, piezoelectric balance, analytical balance, two-pan balance, one-pan balance; postal scale, baby scale.    [Science of gravity] statics.    ... show more

Roget 321: density, solidity; solidness etc. adj.; impenetrability, impermeability; incompressibility; imporosity^†; cohesion etc. 46; constipation, consistence, spissitude^†.    specific gravity; hydrometer, areometer^†.    condensation; caseation^†; solidation^†, solidification; consolidation; concretion, coagulation; petrification etc. (hardening) 323; crystallization, precipitation; deposit, precipitate; inspissation^†; gelation, thickening etc. v.. indivisibility, indiscerptibility^†, insolubility, indissolvableness.    solid body, mass, block, knot, lump; concretion, concrete, conglomerate; cake, clot, stone, curd, coagulum; bone, gristle, cartilage; casein, crassamentum^†; legumin^†.    superdense matter, condensed states of matter; dwarf star, neutron star.    ... show more