The definition of an idea can by quite broad. Like many words in a language, an idea can encompass many different concepts, and there is probably no single definitive definition for the word.
Here are some possible ways to define an idea:
(1) A new thought that arises after thinking
(2) A new way of behaving or performing
(3) A technological invention
(4) A scientific discovery
(5) A better or clearer understanding of a previously known concept
(6) A way of approaching the world
What are your thoughts on the meaning of an idea ?