guideline
n. countable B2 Upper Intermediate Oxford US //ˈɡaɪdˌɫaɪn// UK //ɡˈaɪdlaɪn// guide·line
n. a rule or piece of advice that tells you how to do something correctly. It is usually a suggestion rather than a strict law.
n. a general rule, principle, or piece of advice. Often used in plural to describe a set of non-binding instructions for conduct or procedure.
The government issued a new guideline for healthy eating.
The company provides a clear guideline for how employees should handle customer complaints on social media.
While these ethical guidelines are not legally enforceable, they serve as a vital framework for researchers navigating the complexities of human subject trials.
From guide + line.
Usage
Commonly used in the plural form ('guidelines') when referring to a complete set of instructions.