I was being humorous/pithy. I meant e.g. the difference between "property" (the dictionary word) and "property" (the programming word, which is a domain-specific usage of the dictionary word) and "property" (as in Property-Based Testing, an even more domain-specific usage). It's analogous to the concept of regular nouns vs proper nouns, but not the same (which is why I didn't use the term "proper noun").