Disestablishmentarianism
If you mean a word for nice, delightful is a possibility.
discreet
Smart can be dangerous when someone is too smart for their own good. Dangerous begins with the letter d.
depressing
delightful dirty dead
There are several adjectives that begin with the letter D that can be used to describe a good person. You could use dutiful, delightful, darling, or diligent.
· vibrant · virgin · virtuous · vivacious · vocal
D:dangerousdauntingdefiantdependabledifficultV:verifiablevigorousvindictivevolatilevulgar
· delicious
Some adjectives that end with D are:blondbloodboldcardboardcoldendgladgoldgroundhardloudmadoldpallidplaidproudroundsadsaladsolidsoundtorridwoodwordworldYou may also use words that end in 'ed', such as chilled, mashed, painted spoiled, etc.
ambitiousbrilliantcourteousdiligent
determineddiligent
desolate