| duff | <botany> The matted, partly decomposed, organic surface layer of forested soils. (09 Oct 1997) |
|---|---|
| Duffy | Blood group system. Single gene locus. (18 Nov 1997) |
| duffy blood-group system | A blood group consisting mainly of the antigens fy(a) and fy(b), determined by allelic genes, the frequency of which varies profoundly in different races; amorphic genes are common. (12 Dec 1998) |