Other forms: primers
Primer is the first coat, which helps the real paint grip. Apply a primer, a coat of primer, primer and topcoat.
It seals a porous surface and gives the topcoat something to hold on to, which is why paint on bare wood or new plaster fails without it. Primer also means an introductory book on a subject, and the cap that fires a cartridge.
1nounprimerThe first coat, which helps the real paint grip.
“Put on a coat of primer before you paint the bare wood.”
2nounmakeupA cream put on the skin before make-up, to help it go on smoothly and last.
“A thin layer of primer stops her foundation sliding off by lunchtime.”
Too few real examples of this word to estimate which sense is commonest.
Medieval Latin primarius, first, gave both the prayer book and the first coat. Prime and primary are relatives.
Middle English
primer
English, today
primer
Built from
From Middle English primer. From Middle English primer, primere, from Medieval Latin primarius and primarium (“prayer book”) possibly via Anglo-Norman - primer (“prayer book”), from prima (“prime the liturgical hour and office”) + -arius and -arium. Its use for schoolbooks derived from the late medieval and early modern use of such prayer books to teach reading.
Etymology from Wiktionary, CC BY-SA