primer

Concise Oxford English Dictionary © 2008 Oxford University Press:
primer1

▶noun

• 1 a substance painted on wood, metal, etc. as a preparatory coat.

• 2 a cap or cylinder containing a compound which ignites the charge in a cartridge or explosive.

• 3 a small pump for priming an engine.

Concise Oxford English Dictionary © 2008 Oxford University Press:
primer2

▶noun a book providing a basic introduction to a subject or used for teaching reading.

– origin ME: from med. L. primarius (liber) ‘primary (book)’ and primarium (manuale) ‘primary (manual)’.