@NaturalMineralWater – You have correctly pointed out that the word ‘theory’ is ambiguous like so many words in natural languages. In terms of the actual word ‘theory’ it’s actually the other way round.
http://en.wikipedia.org/wiki/Theory
A theory, in the general sense of the word, is an analytic structure designed to explain a set of observations. The term is often used colloquially to refer to any explanatory thought, even fanciful or speculative ones, but in scholarly use it is reserved for ideas which meet baseline requirements about the kinds of observations made. In the sciences generally, theories are constructed from elementary theorems that consist in empirical data about observable phenomena. A scientific theory is used as a plausible general principle or body of principles offered to explain a phenomenon.
When people in everyday language use the word ‘theory’ what they usually mean (in a scientific sense) is a hypothesis i.e. an untested theory. Let’s use theory in the scientific sense. Scientific laws are NOT sub par to scientific theories. Theories usually comprise a set of scientific laws (they might be seen as sub par to scientific hypotheses).
Here’s an example:
The theory of relativity comprises many laws such as time dilation or mass-energy equivalence (E=mc^2).
Theories can explain observations by using scientific method. They can also make reliable predictions about the future.
Evolution is another scientific theory. It is well tested and not considered a hypothesis anymore. So when you hear ‘it’s still a theory’ what people mean it’s still a hypothesis which it’s not. It’s a fact. It’s an accepted branch of science.The empirical evidence for evolution is overwhelming, even though we can’t build a time machine to go back 65 millions years. Nucleosynthesis inside of stars is also a proven fact even though we can’t look into the core of our sun.