What does "condense" mean?

Condense: (Chem. & Physics) To reduce into another and denser form, as by cold or pressure; as, to condense gas into a liquid form, or steam into water. Condensed milk, milk reduced to the consistence of very thick cream by evaporation (usually with addition of sugar) for preservation and transportation. -- Condensing engine, a steam engine in which the steam is condensed after having exerted its force on the piston.

Additional senses

  1. 2.To become more compact; to be reduced into a denser form. Nitrous acid is gaseous at ordinary temperatures, but condenses into a very volatile liquid at the zero of Fahrenheit. H. Spencer.
  2. 3.(Chem.) (a) To combine or unite (as two chemical substances) with or without separation of some unimportant side products. (b) To undergo polymerization.
  3. 4.Condensed; compact; dense. [R.] The huge condense bodies of planets. Bentley.

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