condensation

1. Making more solid or dense. 2. The change of a gas to a liquid, or of a liquid to a solid. 3. In psychoanalysis, an unconscious mental process in which one symbol stands for a number of others. 4. In dentistry, the process of packing a filling material into a cavity, using such force and direction that no voids result. [L. con-denso, pp. -atus, to make thick, condense]

- aldol c. formation of an aldol (a β-hydroxy carbonyl compound) from two carbonyl compounds; the reverse reaction is an aldol cleavage; fructose 1,6-bisphosphate aldolase catalyzes such a reaction.

- Claisen c. the formation of a β-keto ester from two esters, one of which has an α-hydrogen atom; malate synthase, citrate synthase, and ATP citrate lyase all catalyze such reactions.

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con·den·sa·tion .kän-.den-'sā-shən, -dən- n

1) the act or process of condensing: as

a) a chemical reaction involving union between molecules often with elimination of a simple molecule (as water) to form a new more complex compound of often greater molecular weight

b) the conversion of a substance (as water) from the vapor state to a denser liquid or solid state usu. initiated by a reduction in temperature of the vapor

2) representation of several apparently discrete ideas by a single symbol esp. in dreams

3) an abnormal hardening of an organ or tissue <connective tissue \condensations>

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con·den·sa·tion (kon″dən-saґshən) [L. condensare to pack close together] 1. compression. 2. the packing of dental filling material into a prepared tooth cavity. 3. a mental process in which one symbol stands for a number of components and contains all the emotion associated with them. 4. conversion from the gaseous state to the liquid state (liquefaction) or solid state (solidification).