(organic chemistry) Any of several polycyclic cagelike hydrocarbons whose underlying structure of carbon atoms is that of one of the Platonic solids; not all are possible, either due to excessive strain, or to valency considerations.

(chemistry) monatomic hydrogen that exists transiently after the reduction of a hydrogen ion; generated from zinc and hydrochloric acid; it is a strong reducing agent

All the liquid waters of the Earth, as distinguished from the land and the gases of the atmosphere.

(chemistry) A weak bond in which a hydrogen atom in one molecule is attracted to an electronegative atom (usually nitrogen or oxygen) in the same or different molecule.

(chemistry) To bond to another species by means of hydrogen bonds. E.g. Water hydrogen bonds with itself.

Any of several shrubs, of the genus Hydrangea, having large clusters of white, pink or blue flowers

(chemistry) A compound for which no simple structure can be written, but which actually has a structure midway between two simple ones - normally one polar and one nonpolar.

Someone or something that has two sides: one good (the "Dr. Jekyll") and one bad (the "Mr. Hyde").

Alternative form of hybridization

(genetics) a phenomenon in which high transposon mobility causes reduced fertility in hybrid progeny