dis·tem·per 2 
(dĭs-tĕmpər)
(dĭs-tĕmpər)n.
1.
a. A process of painting in which pigments are mixed with water and a glue-size or casein binder, used for flat wall decoration or scenic and poster painting.
b. The paint used in this process.
2. A painting made by this process.
tr.v. dis·tem·pered, dis·tem·per·ing, dis·tem·pers
1. To mix (powdered pigments or colors) with water and size.
2. To paint (a work) in distemper.
[Middle English distemperen, to dilute; see DISTEMPER1.]