That is such a great word.
In my world it always meant anything. Whatever. It could be the answer to a choice:beans or corn? Whatever.
It could be the beginning of a discussion: Whatever were you thinking, or in my southern mind, thinkin'? I wanted to see if the tree limb would hold my weight. Really? It's an inch around. I know, but just had to try. Whatever.
As you can see, it also was an ending to a discussion.
Today a lot of young people, read that anyone under the age of 40, use it for everything.
"Take out the trash." " Whatever."
"Time to get up for school." "Whatever."
" You need an operation." "Whatever."
See? You can use it as an expression of disinterest, acceptance or denial. It works.
So until next time enjoy your life. Whatever.