catastrophic
The definition for catastrophic is "Relating to extreme misfortune." Used in a sentence: The effects of the massive hurricane were catastrophic.
civility
The definition for civility is "Politeness." Used in a sentence: The usually unruly Thomas acted with great civility when his favorite uncle visited.
defiant
The definition for defiant is "Showing bold resistance." Used in a sentence: The defiant toddler refused to leave the park.
extant
The definition for extant is "Currently existing." Used in a sentence: Some consider Clint Eastwood the greatest extant American director.
melee
The definition for melee is "A tumultuous fight among several people." Used in a sentence: After the game, a melee broke out between fans of the opposing teams.