Someone
1. Engaged in academia and research
2. Smart, well-educated, and knowledgeable in many fields
3. Prefers long conversations and explanations rather than short
4. In universities to actually learn and research not just for getting a degree
Most nerds/geeks aren't actually becoming researchers in any topic or getting involved in academia. They leave for jobs or business, especially engineers/doctors. A medical scientist or bioscientist is actually very different than a doctor.