BM
Abbreviation for 'black male' used by doctors as shorthand when jotting down the results of their physical examination.
For example, WDWNBM = well developed, well nourished black male; WDWNBM = well developed, well nourished white male; WDWNWF = well developed, well nourished white female; WDWNBF = well developed, well nourished black female; etc.
The abbreviation 'BM' in both lay and medical parlance also stands for 'bowel movement.'