/ ˈgaɪdlaɪn; NAmE / noun
1.
guidelines [ pl. ] rules or instructions that are given by an official organization telling you how to do sth, especially sth difficult :
The government has drawn up guidelines on the treatment of the mentally ill.
2.
[ C ] something that can be used to help you make a decision or form an opinion :
The figures are a useful guideline when buying a house.