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 demean is "To lower status." Used in a sentence: The embarrassing photograph demeaned the candidate in the eyes of the voters.

The definition for disconcert is "To throw into confusion." Used in a sentence: Jennifer's outspoken criticism of the meal disoncerted the waiter.

The definition for implausible is "Unbelievable." Used in a sentence: Claudia's implausible excuse failed to convince her teacher.

The definition for onset is "Beginning." Used in a sentence: Crocuses bloom at the onset of spring, sometimes even before the snow melts.