Usually ground rules. basic or governing principles of conduct in any situation or field of endeavor: the ground rules of press conferences.
Sports. any of certain rules specially adopted, as in baseball and softball, for dealing with situations or circumstances arising chiefly from the particular nature of the playing area or the interference of spectators.
Basic Spelling Rules ExplainedYou can teach yourself to be a better speller. It is important to realize that learning to spell is a process that is never complete. Spelling is something that everyone has to pay attention to and keep working at it. BASIC SPELLING RULES Short-Vowel Rule: When one-syllable words have a vowel in the middle, the vowel usually has a short sound. Examples: cat, dog, man, …
Origin of ground rule
An Americanism dating back to 1885–90
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for ground rule
a procedural rule or principle
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012