(organic chemistry) Any cyclophane in which the para positions of a benzene ring are connected by a bridge of at least 10 atoms.

(chemistry) Any compound containing a cation of general formula R₄As⁺; the arsenic analogue of quaternary ammonium compounds.

(chemistry) any polycyclic compound having the form of a cage

(chemistry) Any compound having two or more rings interconnected like the links of a chain, without a covalent bond.

(chemistry) any compound of general formula RN=N-NR₂ where not all R = H

(chemistry) any compound of general formula R₂C=N⁺=N⁻

(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

(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.