The definition for combustion is "Act of burning." Used in a sentence: Campers must use fire with great caution to prevent combustion of the parched brush. The definition for extol is "to praise highly.", the definition for placebo is "An inactive substance used in medical testing.", and the definition for corroborate is "To support with evidence."

The definition for curtail is "To make less." Used in a sentence: Doreen decided to curtail her spending after she bounced a check. The definition for cunning is "showing clever insight.", the definition for rail is "To scold in harsh language.", and the definition for rancorous is "Marked by deep ill–will."

The definition for gravity is "Importance, significance." Used in a sentence: Understanding the gravity of his error, Ken offered his humblest apology. The definition for naive is "lacking worldy wisdom.", the definition for brandish is "To shake or wave menacingly.", and the definition for prudent is "Marked by wisdom, shrewd."

The definition for disdain is "Feeling of contempt." Used in a sentence: The arrogant writer did not hide his disdain for his uneducated dinner companion. The definition for ethical is "conforming to accepted standards.", the definition for appalling is "Inspiring dismay or disgust.", and the definition for buffer is "Protective barrier."

The definition for fraud is "Trick." Used in a sentence: The con man's fraud involved selling swampland to gullible investors. The definition for heed is "to pay attention to.", the definition for clairvoyance is "Ability to see things beyond ordinary perception.", and the definition for polarize is "To break up into opposing groups."