Direct line is commonly used to describe a straight route or connection between two points. However, if you want to add variety to your writing, there are many synonyms that can be used in place of direct line. These include: straight path, unobstructed route, clear trajectory, uninterrupted course, unhindered passage, linear path, direct route, seamless line, unbroken connection, and straightaway link. By using different synonyms for direct line, you can add a unique flair to your writing and keep your readers engaged. Experiment with different phrases to find the synonym that best fits your intended meaning and tone.