WHAT DOES THE WORD REALITY MEAN?

I have focused my thought on this question for a long, long time, having come to it while inquiring the rational foundations of Psychology, of Psychopathology and of Clinical Psychiatry. Reality in these fields is mostly taken as an axiom, i.e., as an evident for itself notion.
Let's just take a look at some common statements regarding this:

1) "John's self-image is not real";
2)"Paul's behavior is a consequence of his unreal perceptions and the thoughts he derives from them";
3) "A schizophrenic person may have hallucinations, which are often accompanied by ideas of being chased in the absence of any basis in factual reality".

Despite its obvious central role, the word "reality" in such sciences, indeed, does not refer to any clear and well-founded concept, but rather to a vague, intuitive notion.
This widespread use of consensual notions on its meaning represents a quite disappointing limitation in a so crucial to human life sciences. Should scholars seek exhaustively for a more solid foundation for their field?
Philosophers of Science say human beings will forever be capable of catching any absolute truth, since these, whether existing, could be accessible only to an Absolute Being. All knowledge at our possible reach must be come as partial, relative, provisional sey of truths.
Aristotle's representation of the solar System was discarded by Galieo Galilei and other renaissance astronomers. Newtonian physics came to be surpassed by Einstein's one. This latter's theories are sure extremely valuable in contemporary physics, and so will be for a long time, but it is not difficult to conceive that sooner or later another scientific revolution will come to regard Einstein as an outdated genius, similarly to the way we regard now those who before him were unaware of time's relativity, taking it for an absolute, homogenous entity.
Well, being provisional truths the only contents of all kinds of knowledge, a fortiori all our theories must be regarded as 'fishnets' through which outside world (the fish) data are caught by our understanding as efforts to keep us alive and to perpetuate our species.
Empirical data gathered by sciences are must be objective, reproducible by other scientists, but each and every human being lives from his/her own 'fishnet', having many other sources besides those mentioned objectifiable theories.
Absolute, ultimate reality escapes always from our nets, whatever they be.