Q

quagmire - noun a soft wet area of low-lying land that sinks underfoot
queasy - adj. causing or fraught with or showing anxiety; feeling nausea; feeling about to vomit; causing or able to cause nausea
quid pro quo - noun something for something; that which a party receives (or is promised) in return for something he does or gives or promises
quixotic - adj. not sensible about practical matters; unrealistic