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 prudent is "marked by wisdom, shrewd.", the definition for iridescent is "Having a lustrous or attractivve quality.", and the definition for repentant is "Feeling regret."

The definition for retroactive is "effective as of a prior time or condition." Used in a sentence: The retroactive law made even past infractions punishable. The definition for immoderate is "beyond usual or proper limits.", the definition for placebo is "An inactive substance used in medical testing.", and the definition for exception is "A case to which the rule does not apply."

The definition for implausible is "Unbelievable." Used in a sentence: Claudia's implausible excuse failed to convince her teacher. The definition for cunning is "showing clever insight.", the definition for rail is "To scold in harsh language.", and the definition for scapegoat is "Someone who bears the blame for others."

The definition for untenable is "Not able to be defended." Used in a sentence: Rashid made the untenable statement that George Washington was the second president of the United States. The definition for elate is "to fill with joy.", the definition for archetypal is "Characteristic of the original model or perfect example.", and the definition for revoke is "To cancel by taking back."

The definition for genial is "Sympathetic, friendly." Used in a sentence: The genial host warmly greeted his many guests. The definition for accentuate is "to emphasize.", the definition for liability is "A person or thing whose presence or behavior is likely to cause embarrassment or put one at a disadvantage.", and the definition for recrimination is "A retaliatory accusation."