Say what? Words have meaning because they're assigned meaning by users. It is not a matter of what people think. You can think all day long that "red" means an ice cream sundae is about to land on your head, but this doesn't make it so.
Word meanings are, if not universal, then very close to it. We all have to accept the same meanings, or we can't communicate. All you're doing is failing to understand what some words mean, and no matter what you think, they still do not mean what you think they do. Yu get it wrong, and rather than looking it up, you justify it by saying it means whatever you think it means. Not hardly.
You can think all day long that "everyday" means whatever you wish, but as soon as you use it in print, editors will correct you, if they bother reading another word.
If I read one of your manuscripts, I have no idea what you were thinking. I do know what the words actually mean, however, and if it seems you do not, you'll get an instant rejection.
I have never claimed that the word means whatever I think it means. In fact, I have looked it up in several dictionaries now. All agree in assigning multiple senses to the word. Some definitions are along the lines of "daily," i.e. they are more or less the same as what I originally took to be the word's main meaning. Other definitions are along the lines of "ordinary," i.e. they are more or less the same as what you take to be the word's meaning.
Many words have multiple senses. This isn't an either/or matter.
For example, here is the entry in the Random House Unabridged Dictionary (second edition, 1993):
everyday,
adj. 1. of or pertaining to every day; daily:
an everyday occurrence. 2. of or for ordinary days, as contrasted with Sundays, holidays, or special occasions:
everyday clothes. 3. such as is met with every day; ordinary; commonplace:
a placid, everyday scene.
Incidentally, you may notice that whenever sense #1 is applicable, sense #3 is also applicable. Something that is met with literally every day is automatically ordinary. So I don't think I need to worry too much about using the word in sense #1 and offending an editor who is wedded to sense #3.
(If anything, it's the converse that might cause a problem. If you write "It was an everyday Christmas," meaning "It was an ordinary Christmas," that will come across as very strange to anyone who is attached to sense #1. "It was an everyday Christmas" is still something I wouldn't say, but I will now accept that there is a sense in which the sentence is legitimate.)
I said "Thought is what creates meaning," and that statement may have been misinterpreted as a claim that words mean whatever I think they mean. So let me try to clarify the general point.
In my opinion, people assign meanings to words
by thinking about them in a particular way. If
everyone thought "red" meant that an ice cream cone was about to land on your head, that would indeed be what the word meant. If some particular subculture thought that was what "red" meant, then the word would have that meaning within that subculture.
Lots of subcultures use words in nonstandard ways. Sometimes they may deserve criticism for doing so. As an extreme case, you can imagine a lone eccentric who assigns the meaning to "elephant" that others assign to "chair." (The example comes from another post in this thread.) I entirely agree that this eccentric individual is making a serious mistake. But his mistake is not about the meaning of the word "elephant." He is perfectly correct about the meaning of the word--for himself. Rather, his mistake is in thinking that any desirable consequences might come from assigning a meaning to the word in such an unusual way.
In less extreme cases, things are a lot less clear-cut. I hope you don't mean it quite literally when you say "we all have to accept the same meanings." That almost sounds like a demand that everyone in the world should speak just one dialect of one language. Are the British doing something wrong when they assign a different meaning to the word "football" than Americans do?
If what you really mean is that all speakers of a particular dialect must accept the same meaning for a word, I still can't accept that as anything close to an absolute statement. Many words have several different senses, with different senses being used in different contexts. (For example, there are words with specialized technical senses. In physics, "color" sometimes has a meaning very different from the one it ordinarily has.) Sometimes that does indeed cause confusion, and it's something you have to watch out for. But it's a significant part of language, and watching out for it isn't the same as trying to eliminate it. So I don't think I can agree with your statement that word meanings are close to universal.
"Everyday" is an example of the general point, but there are plenty of other examples. I could bring in some other words now, but I've gone on for long enough.