Noun
(metaphysics) An idea separated from a complex object, or from other ideas which naturally accompany it; as the solidity of marble when contemplated apart from its color or figure.
Used other than figuratively or idiomatically: see abstract, idea.
Source: en.wiktionary.orgRevenge is a particularly interesting concept, especially the notion of whether or not it exists outside of just an abstract idea. Christopher Nolan
There's no way that scientists can ever rule out religion, or even have anything significant to say about the abstract idea of a divine creator. Brian Greene
Even the recognition of an individual whom we see every day is only possible as the result of an abstract idea of him formed by generalization from his appearances in the past. James Frazer
Once having proclaimed our loyalty to the abstract idea that all men are created equal, we do everything in our power to prove ourselves unequal. Among the world's peoples, none other belongs to so many clubs, associations, committees and secret societies. Lewis H. Lapham
No cause, no God, no abstract idea can justify the mass slaughter of innocents. Edward Said
In a flash I knew that the word was the name of the process that was going on in my head. This was my first conscious perception of an abstract idea. Helen Keller