noun, plural abacuses, abaci. [ab-uh-sahy, -kahy, uh-bak-ahy] /ËÃ¦b ÉËsaÉª, -ËkaÉª, ÉËbÃ¦k aÉª/ (Show IPA) 1. a device for making arithmetic calculations, consisting of a frame set with rods on which balls or beads are moved. 2. Architecture. a slab forming the top of the capital of a column. Origin of abacus.
Sulfate is any salt or ester made up of sulphuric acid. Sulfide is used to describe any of three types of chemical compounds that contain sulfur. Sulfite is sulfur dioxide, or SO2.
Sulfa drugs are based on or derived from the chemical sulfonamide which contains a sulfur dioxide group in each molecule. In my body, about 15% of the drug is digested to release sulfur dioxide and cause a headache.