A to Z Challenge: Q

For me Q is always one of the hardest letters, what about you guys?

Quash
Definition: put down by force or intimidation.
Sentence: More than 500 people are thought to have been killed since mid-March as the security forces try to quash dissent. 
            — BBC (May 7, 2011)

Quiescent
Definition: being quiet or still or inactive.
Sentence: Under normal conditions, only a fraction of these blood-forming stem cells are active; the rest are deeply quiescent – asleep. 
              — The Guardian (Jan 17, 2011)

Quintessence
Definition: the most typical example or representative of a type.
Sentence: This composition, in many ways the most wonderful single piece we have from Chopin, is the quintessence of his genius.
                — Walter Raymond Spalding

Quisling
Definition: someone who collaborates with an enemy occupying force.
Sentence: Naturally enough, the attitude taken up by the Christians earned them fresh attacks from the Quisling followers. 
               — Johan Martinus Snoek

Quixotic
Definition: not sensible about practical matters; idealistic and unrealistic.
Sentence: Granted, Latin American integration is an elusive if not quixotic goal: the region stretches farther than Africa, and its nations' interests are just as balkanized.
                  — Time (Dec 4, 2011)