NCI Dictionary of Cancer Terms
The NCI Dictionary of Cancer Terms features 8,018 terms related to cancer and medicine.
- listen (sy-KOH-sis)
- A severe mental disorder in which a person loses the ability to recognize reality or relate to others. The person is not able to cope with the demands of everyday life. Symptoms include being paranoid, having false ideas about what is taking place or who one is, and seeing, hearing, or feeling things that are not there.