Supplement
SUP'PLEMENT, noun [Latin supplementum, suppleo; sub and pleo, to fill.]
1. Literally, a supply; hence, an addition to any thing by which its defects are supplied, and it is made more full and complete. The word is particularly used of an addition to a book or paper.
2. Store; supply. [Not in use.]
3. In trigonometry, the quantity by which an arc or an angle falls short of 180 degrees or a semicircle.