goober used by radiologists to denote an area of radio-opacity due to contrast on CT, and by nuclear medicine physicians to denote an area of high FDG uptake resulting in intense positron emission in PET. Typically more focal and delineated than schmutz (q.v.)

schmutz 1. used by radiologists to denote an area of diffuse opacity on plain X-ray or CT, often applied to infiltrates, malignant effusions, abscesses, and other non-homogenous fluid collections. 2. non-homogenous material often found smeared across an intern's face after he/she has eaten their meal in the requisite five minutes.