debonair — refined, affable, approachable, urbane
All the ladies had their eye on the debonair gentleman at the cocktail party.
deface — to disfigure
It is wrong to deface the property of others.
defame — to attack the reputation, to accuse a person falsely
Make sure you have your facts before you defame anyone.
dastardly — cowardly, mean, malicious
Hurting helpless children is a dastardly act.
declivity — downward slope
The stock market was showing signs of declivity.
decrepit — weakened, worn out, broken down
The house was getting decrepit since the Smith's had no money for much needed repairs.
deft — skillful, expert
She was quite deft at roller skating.
deleterious — injurious, harmful
Sticking your foot out in front of someone that can't see it is a deleterious thing to do.
delirious — suffering from delirium
The medication was making him delirious as he told us he was seeing flying pigs.
delude — to mislead, to deceive
If you delude me, I won't be able to trust you.
demeaning — lacking in honor or integrity, humiliating
Being demeaning to a waitress is cruel since she's in a subservient position.
depleted — drained, used, no longer sufficient
All this studying has depleted my energy.
deranged — driven insane, insane
The deranged housewife cut up all her clothes and set her house on fire.
deride — to ridicule
I'm not a fan of reality shows that deride the participants.
desiderate — to wish for, to miss
I often desiderate the years of my youth.
diabolical — evil
The youth often had diabolical thoughts about his classmates.
diaphanous — transparent, flimsy
The glass had a diaphanous appearance and I was afraid it would break easily.
diffident — timid, shy, reserved, modest
She was diffident on the beach and would not take off her coverup.
discernible — able to be perceived, obvious
The scratch was barely discernible on the new car.
disparage — to speak disrespectfully
I am never impressed when a friend disparages another.
distinguish — to notice as different
In this light it's hard to distinguish the blue from the purple.
divergence — moving apart, diverging
Our differing careers had a big role in the divergence of our relationship.
docile — teachable, willing to be supervised
Although huge and threatening-looking, the pit bull was very docile.
doleful — causing grief, filled with sadness
The letter she got in the mail caused a doleful expression on her face.
dubious — doubtful
It was dubious at best that Jeff would pass the test as he didn't study at all.