prim ‧ er /ˈpraɪmə $ -ər/ BrE AmE noun
1 . [uncountable and countable] paint that you put on the surface of wood, metal etc before you put on the main layer of paint
2 . [countable] a tube that contains explosive and is used to fire a gun or explode a bomb
3 . [countable] American English a book that contains basic information about something
primer on/of
a primer on Italian wines
a primer of good management techniques
4 . [countable] old-fashioned a school book that contains very basic facts about a subject