conception, construct, idea, notion, premise, principle, theory, aspect, conceptualization, approach, more...

reality, fact, actuality, existence, certainty

nominal, ordinal, interval, ratio, fuzzy, more...

new, basic, self, important, general, whole, very, key, central, abstract, original

general idea,   basic idea,   the idea of,   idea of,   an idea,   given idea,   the idea that,   unifying idea,   certain abstraction,   thing or idea