These words describe a way of doing something that you have in your mind.
One of the most common words for this isidea.
I've got an idea - why don't we ask John for help?
No one wants to discuss these ideas right now.
That's a good idea.
An idea about how to do something is often described as aplan,thought, orsuggestion.
The plan is to hire a car when we get there.
Have you had any thoughts on presents for your mother?
Have you got any suggestions for improvements?
A sudden, clever idea is sometimes described as abrainwavein UK English and abrainstormin US English.
UKI wasn't sure what to do and then I had brainwave - I could ask Anna for help.
USShe was stuck until she had a brainstorm and the solution came to her.
The nountheoryis sometimes used to describe a set of ideas intended to explain something.
He was giving a lecture on Einstein's theory of relativity.