(inorganic chemistry) The ionic base, NH₄⁺OH⁻, obtained by dissolving ammonia in water.

(inorganic chemistry) An alkali, LiOH, used in gas-purification systems in spacecraft, submarines etc, and in the preparation of lithium soap.

(inorganic chemistry) A strong, caustic alkali (NaOH) used in the manufacture of soap, detergents, paper, textiles and having many other industrial applications.

(inorganic chemistry) Alternative spelling of aluminium hydroxide

(meteorology) A hygrometer consisting of two thermometers, the bulb of one of which is kept wet and shows a lower temperature; the relative humidity is obtained from the two temperatures using tables.

(physics, chemistry, botany) Readily taking up and retaining water, especially from the atmosphere.

(obsolete, chemistry) phosphine

(physics) An approximation to a wave function made by taking a linear combination of simpler functions

Using hydraulics.

(physics) An orbital formed by the combination of multiple atomic orbitals on the same atom