Emily Dickinson Lexicon

DE-ROG'A-TO-RY, a.

1. Detracting or tending to lessen by taking something from; that lessens the extent, effect or value; with to. Let us entertain no opinions derogatory to the honor of God, or his moral government. Let us say nothing derogatory to the merit of our neighbor.
2. A derogatory clause in a testament, is a sentence or secret character inserted by the testator, of which he reserves the knowledge to himself, with a condition that no will he may make hereafter shall be valid, unless this clause is inserted word for word; a precaution to guard against later wills extorted by violence or obtained by suggestion. – Encyc.