Initialism of unified school district. / Initialism of United States dollar.

(medicine) A device with a canister holding a medicine in a dry powder form, ready to be sucked/sprayed out as aerosols, with the purpose to be inhaled by a patient into the lungs. The device is co...

(obsolete) The quality or state of being prefident.

(fencing) A counter-attack that attempts to take advantage of an uncertain attack