Here are some examples:
* Doctor: This word originally meant "teacher" but has evolved to refer to someone who holds a doctorate degree (a document certifying the highest level of education) or a medical professional who is trained in a specific area.
* Documentation: This word refers to the process of creating and maintaining documents.
* Documentary: A film or other media that presents factual information.
* Docent: A guide who provides information and instruction, often in a museum or art gallery.
* Doctrines: A set of beliefs or principles, often written down in a document.
* Dockets: A list of cases to be heard in a court, often written down and organized in a document.
However, "doc" can also appear in informal contexts, like when referring to a doctor or when someone is called "Doc."