parallel rule

noun

variants or parallel ruler

: an instrument for drawing a line parallel to another or a series of parallel lines: such as

a

: a flat rule running on a pair of rollers in one of its sides

b

: a pair of straightedges connected by two equal parallel links so that one straightedge can be moved only parallel to the other

The Ultimate Dicitonary Awaits

Expand your vocabulary and dive deeper into language with Merriam-Webster Unabridged.

1. Expanded definitions
2. Detailed etymologies
3. Advanced search tools
4. All ad-free

Discover what makes Merriam-Webster Unabridged the essential choice for true word lovers.

Start Your Free Trial Now