aerate
The definition for aerate is "To supply with air." Used in a sentence: Every spring, Soloman used his tiller to aerate the compact soil.
appalling
The definition for appalling is "Inspiring dismay or disgust." Used in a sentence: Hector found his roommate's habit of leaving his dirty socks on the floor appalling.
derivative
The definition for derivative is "Lacking originality." Used in a sentence: Critics panned the movie as a derivative version of last year's Best Picture.
extenuating
The definition for extenuating is "Partially excusing." Used in a sentence: The extenuating circumstance of Calvin's illness caused the teacher to excuse his lateness.
placebo
The definition for placebo is "An inactive substance used in medical testing." Used in a sentence: Tom, who had taken the placebo, found that his allergy symptoms did not go away.