No definitions found for 'do duty'
Perhaps one of these:
dead ahead,
dodded,
deadwood,
dotted,
deduit,
dotehead,
doodad,
day-to-day,
dated,
diiodide,
deitate,
due date,
dead head,
deadhead,
doted,
dutied,
dittied,
deodate,
do without,
dededo,
dead heat,
dieted