(chemistry) any compound having the general formula R-N₂⁺ X⁻, especially one in which R is an aryl residue; they are important as intermediates in the production of azo dyes

(obsolete, organic chemistry) Synonym of oxime

(chemistry) any compound in which a metal atom is located between the faces of two planes of atoms, especially between two rings

(organic chemistry) Any polycyclic compound having a single atom (usually carbon) as the only common member of two rings.

A microscope with more than one lens, arranged so that the image formed by one lens is further magnified by another.

(fencing) An attack consisting of more than one feint.

A visual organ found in arthropods such as insects and crustaceans. It consists of one to thousands of tiny independent photoreception units.

plural of compound eye

(chemistry) Any compound containing atoms of three different elements

(chemistry) Any substance formed by the union of two or more chemical elements in a fixed ratio, the union being a chemical bond. / (informal, proscribed) Any single substance, either compound or element