Something that is linier is arranged in a straight line or follows a straight path.
Linier things are often seen as organized and easy to understand.
Examples:
The linier row of trees looked very neat.
The linier path led us straight to the beach.
She drew a linier picture of a house.
The linier pattern on his shirt made him look like a zebra!
The linier road went on and on for miles.
The linier arrangement of books on the shelf made it easy to find what I needed.