The definition for retroactive is "effective as of a prior time or condition." Used in a sentence: The retroactive law made even past infractions punishable. The definition for salvage is "to save from ruin.", the definition for regale is "To amuse.", and the definition for foil is "One that enhances or underscores by contrast."

The definition for commemorate is "To mark by a ceremony." Used in a sentence: Each year, the Franklins commemorate their anniversary by visiting the site of their first date. The definition for placebo is "an inactive substance used in medical testing.", the definition for curtail is "To make less.", and the definition for derelict is "Abandoned."

The definition for equitable is "Fair and equal." Used in a sentence: The judge made an equitable decision dividing the estate evenly among the sisters. The definition for colossal is "immense, enormous.", the definition for abate is "Become less in amount or intensity.", and the definition for onset is "Beginning."

The definition for buffer is "Protective barrier." Used in a sentence: The dense trees acted as a buffer against the heavy rain. The definition for stern is "harsh, severe.", the definition for belated is "Past the normal or proper time.", and the definition for procrastinate is "To put off intentionally."

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. The definition for advantageous is "giving an advantage.", the definition for oblivious is "Lacking awareness.", and the definition for futile is "Without purpose, completely ineffective."