Right. We can take that lack of familiarity and introduce some meaning: if we're producing some document, course, etc, then we simply state our intended sense of the word, or assert a more precisely qualified phrase that matches our intended meaning. Without explicitly defining terms in a formal context (e.g., a document), we will face the fact that the more generic the word, the more open to interpretation and variability of senses it will engender by readers. That is not only common to language, but to highly generic words (e.g. broad category terms). Likewise for 'conceptual model'.