'Clean' vs 'Clear'
Clean, as adjective, means:
- Free from dirt, marks, or stain (the room was spotlessly clean)
- Morally uncontaminated; pure; innocent (clean living)
- Free from irregularities; having a smooth edge or surface (a clean fracture of the leg)
Clear, as adjective, means:
- Easy to perceive, understand, or interpret (the voice on the telephone was clear and strong)
- Free of anything that marks or darkens something (the clear glass of the French windows; the day was fine and clear; I looked into her clear gray eyes)
- Free of any obstructions or unwanted objects (with a clear road ahead, he shifted into high gear)
You could be confused between the first meaning clean and the second meaning of clear. A clean glass is a glass that is not dirty; a clear glass is a glass that doesn't contain any substances that make it opaque.
They have subtile differences. "Clear the table", means to take away plates or papers, while "clean the table" means to wipe it. "Cleaning up" may include both clearing and cleaning in the general sense.
clean an object = remove anything that makes it dirty
clear an object = remove anything that hinders it from being obvious