buffer
The definition for buffer is "Protective barrier." Used in a sentence: The dense trees acted as a buffer against the heavy rain.
incisive
The definition for incisive is "Impressively direct and decisive." Used in a sentence: Samir's incisive leadership made him the natural choice for president of the company.
iridescent
The definition for iridescent is "Having a lustrous or attractivve quality." Used in a sentence: The movie star's iridescent presence charmed even the hardened reporter.
redouble
The definition for redouble is "To make twice as great." Used in a sentence: As the sun began to set, Brittany redoubled her effort to find the necklace she had dropped in the field.
unscrupulous
The definition for unscrupulous is "Lacking principles." Used in a sentence: The unscrupulous salesman was fired for lying to his customers.