SO3 may refer to
*
Sulfur trioxide, a chemical compound of sulfur and the anhydride of sulfuric acid
*
Sulfite, a chemical ion composed of sulfur and oxygen with a 2− charge
*
SO(3)
In mechanics and geometry, the 3D rotation group, often denoted SO(3), is the group of all rotations about the origin of three-dimensional Euclidean space \R^3 under the operation of composition.
By definition, a rotation about the origin is a tr ...
, the special orthogonal group in 3 dimensions; the rotations that can be given an object in 3-space
*''
Star Ocean: Till the End of Time'', the third main game in the ''Star Ocean'' series
*A
staff officer
A military staff or general staff (also referred to as army staff, navy staff, or air staff within the individual services) is a group of officers, enlisted and civilian staff who serve the commander of a division or other large military ...
of the third class, usually a
junior officer
Junior officer, company officer or company grade officer refers to the lowest operational commissioned officer category of ranks in a military or paramilitary organization, ranking above non-commissioned officers and below senior officers.
The ...
*
Special Operations 3 - Planning, of
SOE (Special Operations Executive, British, World War II)
*''SO3'', a
TL9000 metric defined as the number of service impact product-attributable outages per NU (normalization unit) per year
{{Letter-Number Combination Disambiguation