SO4 may refer to:
*
National Identification Service, a department of the London Metropolitan Police which provides a range of support services on behalf of the Metropolitan Police and other police forces
* ''
Star Ocean: The Last Hope'', an action role-playing video game developed by Tri-Ace and Square Enix
*
Sulfate
The sulfate or sulphate ion is a polyatomic anion with the empirical formula . Salts, acid derivatives, and peroxides of sulfate are widely used in industry. Sulfates occur widely in everyday life. Sulfates are salts of sulfuric acid and many ...
, , in chemistry, an inorganic ion or a salt of sulfuric acid.
* SO4 is an acronym for remembering the function of the fourth cranial nerve, the
trochlear nerve
The trochlear nerve (), ( lit. ''pulley-like'' nerve) also known as the fourth cranial nerve, cranial nerve IV, or CN IV, is a cranial nerve that innervates just one muscle: the superior oblique muscle of the eye, which operates through the pu ...
, which control the
superior oblique muscle of the eye.
* SO(4), the group of
rotations in 4-dimensional Euclidean space
In mathematics, the group of rotations about a fixed point in four-dimensional Euclidean space is denoted SO(4). The name comes from the fact that it is the special orthogonal group of order 4.
In this article '' rotation'' means ''rotational ...
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