guideline-n; 2 Senses

Sense Number 1: a reference line used to align lettering

Commentary: GUIDELINE[+form][+line][+reference][+alignment]

The painter used a guideline to keep the lettering straight on the sign.
I used a yardstick as a guideline to cut a straight line across the fabric.

WordNet 3.0 Sense Numbers: 1

Sense Number 2: principles, regulations

Commentary: GUIDELINE[+entity][+symbolic][+idea][+principle][+regulation]
NOTE: specifies a course of action, plan, rule of thumb

The school has set out stricter guidelines for the dress code this year.
The president will follow the guidelines set out in the report.
John lets the Golden Rule be his guideline in dealing with others.
The American Dental Association has set forth new guidelines for dental hygiene.

WordNet 3.0 Sense Numbers: 2, 3