A guideline is a rule-of-thumb or suggestion that shows or tells you how to behave. If you want to stay healthy, you might want to follow the government's dietary guidelines. Sample guideline: go easy on the salt.

In the 18th century, guideline referred to an actual line that you drew on fabric before cutting. So for example, if you wanted to cut a piece of linen to make a dress, you'd draw a guideline on it first to make sure the incision would be straight. The line guided your cut; over time, the word became a metaphor for a guide to any sort of action.

Definitions of guideline
  1. noun
    a rule or principle that provides guidance to appropriate behavior
    synonyms: guidepost, rule of thumb
    see moresee less
    type of:
    regulation, rule
    a principle or condition that customarily governs behavior
  2. noun
    a detailed plan or explanation to guide you in setting standards or determining a course of action
    synonyms: road map
    see moresee less
    type of:
    plan, program, programme
    a series of steps to be carried out or goals to be accomplished
    counsel, counseling, counselling, direction, guidance
    something that provides direction or advice as to a decision or course of action
  3. noun
    a light line that is used in lettering to help align the letters
    see moresee less
    type of:
    a mark that is long relative to its width
Word Family

Test prep from the experts

Boost your test score with programs developed by’s experts.

  • Proven methods: Learn faster, remember longer with our scientific approach.
  • Personalized plan: We customize your experience to maximize your learning.
  • Strategic studying: Focus on the words that are most crucial for success.


  • Number of words: 500+
  • Duration: 8 weeks or less
  • Time: 1 hour / week


  • Number of words: 500+
  • Duration: 10 weeks or less
  • Time: 1 hour / week


  • Number of words: 700+
  • Duration: 10 weeks
  • Time: 1 hour / week