Other forms: rulebooks
A rulebook is the booklet setting out how a game is played. Read the rulebook, check the rulebook, a thick rulebook.
Arguments are settled by it, which is why a good one is indexed. Going by the rulebook is also a figure for following procedure exactly, and throwing it out is the opposite.
1nounrulebookThe booklet setting out how a game is played.
“Nobody had opened the rulebook in fifteen years of playing.”
rulebook is a book.
From rule + book.
Etymology from Wiktionary, CC BY-SA