beneficial
The definition for beneficial is "Helpful." Used in a sentence: there is no doubt that eating vegetables is beneficial to one's health.
buffer
The definition for buffer is "Protective barrier." Used in a sentence: The dense trees acted as a buffer against the heavy rain.
fraud
The definition for fraud is "Trick." Used in a sentence: The con man's fraud involved selling swampland to gullible investors.
incongruous
The definition for incongruous is "Not harmonious, incompatible." Used in a sentence: Sadie's cowboy hat was incongruous with her black cocktail dress.
plaudits
The definition for plaudits is "Enthusiastic approval." Used in a sentence: Allison's painting met with plaudits from the critics, who had dismissed her earlier work.