There are a lot of definitions available for these concepts. I’ve found out that Google offers the blandest ones so I’ll use those. You’ll understand why.

a. “An experience involving the apparent perception of something not present”
b. “An extraordinary and welcome event that is not explicable by natural or scientific laws and is therefore attributed to a divine agency.”
c. “An optical illusion caused by atmospheric conditions, especially the appearance of a sheet of water in a desert or on a hot road caused by the refraction of light from the sky by heated air.”

If we follow the ‘dispassionate’ line used by Google we’ll notice that the ‘real’ problem is us, not a. b. or c.

We are the ones who are not able to figure out the source of the perception in a, the explanation for what happens in b and to reconcile what we know with what we see in c.

More than 35 years ago, while in college, I had to study ‘Marxism’. It was considered a science by the communists and all students had to take that class.
“Marxism is a reaction against the idealist thesis that reality consists entirely of minds or spirits and of their experiences or ideas. The materialist conception of history, Marx and Engels contend, postulates the existence of an objective, concrete reality that is independent of human consciousness and is also its determinant“.

For a future engineer, and one that wasn’t particularly concerned with religion, the concept seemed appealing.
Something was nagging me though. In time I understood that Marx was making a huge mistake when conflating ‘objective’ with ‘real’ and individual consciousness with the collective one.
Also what he termed ‘reality’ is not that independent from consciousness as he would liked it to be.

I’ll start with the second idea.

We coined the term/concept of reality.
How’s that for ‘real’ independence?

Is there anything outside my individual knowledge/consciousness?
A lot.
Do I care?
Sometimes yes but most of it is both absolutely inconsequential for me and way out of my grasp. So my accepting its very existence depends decisively on ‘hearsay’ and faith…

Is there anything outside our collective knowledge/consciousness?
Probably yes. Hard to believe that we already know everything, right? Particularly since we discover something new each moment…
‘We discover’?!?
So it’s us who are ‘conquering’ more and more ‘reality’?!?
Wasn’t it supposed to be independent from us?

OK, you probably got it, I won’t bother you anymore with this.

Let me go back to ‘objective’ versus ‘real’.

“Not influenced by personal feelings or opinions.”
“Actually existing as a thing or occurring in fact; not imagined or supposed.”

If we gather five children who haven’t yet seen a tarmac road scorched by the July Sun and take them to Arizona they’ll tell us, excitedly but objectively, that the road is boiling out there near the horizon.
We, the grown ups, know that’s a mirage. For them, it’s a miracle.
For a single child – one that knows the concept, of course – it might seem a hallucination, specially if he doesn’t have another person to speak to about what he sees.

Some independence… But wait, there’s more.

You are reading this on a computer. (If you call it a smartphone you are deluding yourself. It’s a computer that you can also use as a phone). Is it ‘really’ real?
According to Marx, I mean.
If your consciousness hasn’t yet digested effectively its ‘user manual’ that computer is little more than an useless  piece of junk… Not to mention the fact that its processor would still be a little pile of sand if not for an entire string of consciousnesses – from INTEL’s CEO to the driver who delivered it to the assembly plant and they are only a few of those involved in the process.

The fact is that we change the reality around us. We build cities, roads to connect them and power plants so we can cool our homes in summer.

And then we pretend reality is independent from us.
Who’s delusional now?