guideline

As a noun guideline

is a non-specific rule or principle that provides direction to action or behaviour.

As an adjective guidelineless is

without a guideline.

As a noun guideline

is a non-specific rule or principle that provides direction to action or behaviour.

As an adjective nonguideline is

(chiefly|legal) not having or pertaining to guidelines.

As nouns the difference between guideline and snapline

is that guideline is a non-specific rule or principle that provides direction to action or behaviour while snapline is (computing|graphical user interface) a guideline shown while adding an item to a user interface to help align it with other items.