A part that keeps its own shape inside a larger whole. A component can be taken out and still be itself.
Latin componens, present participle of componere (to put together, compose), from com- (together) + ponere (to place); a part that keeps its own shape even while placed inside a larger whole.
A part that keeps its own shape inside a larger whole, and can be lifted out of it and still be itself. Being placeable is the whole of what it is.