What do you mean by zoom lens?

What do you mean by a lens? What are concave and convex lenses? What do you mean by Prnicipal axis, Optical centre and Principal focus and focal length of a lens?

What do you mean by mechanics

What do you mean by diplosome?

What do you mean by ozonolysis ?

What do you mean by one dimensional motion?

What do you mean by holoenzymes?