FWIW, from Concise Oxford (all that is to hand):- Drab:1)Noun. Slut; slattern; prostitute. 2)Adj. Dull, light brown colour. 3)Noun. See drib.
Drib:- Noun. dribs and drabs, small, scattered amounts.
Dram:- Noun. =drachm; small drink of spirit etc.