a method of painting with pigments dispersed in an emulsion miscible with water, typically egg yolk. The method was used in Europe for fine painting, mainly on wood panels, from the 12th or early 13th century until the 15th, when it began to give way to oils.
emulsion used in tempera painting:egg tempera
mid 19th century: from Italian, in the phrase pingere a tempera 'paint in distemper'
tempera in other Oxford dictionaries
Definition of tempera in the US English dictionary