That would be a Precipitate.
For example:
[tex]BaCl_{2} _{(aq)} + H_{2}SO_{4} _{(aq)} -----\ \textgreater \ BaSO_{4}_{(s)} + HCl_{(aq)} [/tex]
Barium Chloride is soluble thus a solution and so is Sulphuric Acid but when the Barium ions merge with the Sulphate ions this cause the product Barium Sulphate deposits from the mixture as a solid (precipitate)