Conceptualization is the name for forming an idea of something — or the idea you end up with after you have done that. When a messy real situation is turned into a clear picture in the mind, that process (and sometimes the picture itself) is a conceptualization. Scientists talk about their conceptualization of a problem; designers talk about the conceptualization of a product before anyone builds it. Though actually, this is a heavy academic word. In everyday English people say the idea of, how we think about, or the way we picture it. British spelling is often conceptualisation, with an s. The sense you were given is “to form an idea,” but this word is the NAME of that forming, not the doing — the doing is conceptualize.