Recently, I have had some good tutoring sessions with someone in high school physics.
Concepts clarified for him when we talked definitions and formulated them from reality — the only way to grasp definitions objectively and logically.
We didn’t throw out some verbal concatenation of words and call it a definition, as is sadly too often done today.
We talked about real things in the real world, found their similarities and differences, classified them, then formulated definitions.
For example, we talked about balls rolling on the floor, ships sailing on the ocean, guided missiles in flight, jet airplanes, automobiles, objects falling, spears thrown, arrows shot, bullets in flight, rocks thrown.
We distinguished horizontal motion, vertical motion, and free fall, from projectile motion, and identified why they were different.
“Projectile motion” and “normal force” have gone from mumbo jumbo to developed, formulated concepts.
Properly formulated definitions are crucial for rational, objective thought — the only kind that is connected to reality and leads to human happiness. It’s not a mere academic matter.