beneficial
The definition for beneficial is "Helpful." Used in a sentence: there is no doubt that eating vegetables is beneficial to one's health.
demeanor
The definition for demeanor is "Behavior towards others." Used in a sentence: Carlos was well liked because of his charming demeanor.
disconcert
The definition for disconcert is "To throw into confusion." Used in a sentence: Jennifer's outspoken criticism of the meal disoncerted the waiter.
penurious
The definition for penurious is "Extrememly stingy." Used in a sentence: Ebenezer Scrooge was most penurious, refusing to give even a penny to charity.
surplus
The definition for surplus is "Excess." Used in a sentence: Trevor decided to freeze the surplus chili for next week's tailgate party.