SO4 may refer to:
*
National Identification Service
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The National Identification Service (NIS; also called SO4 from its Specialist Operations designation) is a department of the London Metropolitan Police which provides a range of support services on behalf of the Metr ...
, 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 ar ...
, , 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 pul ...
, which control the
superior oblique
The superior oblique muscle, or obliquus oculi superior, is a fusiform muscle originating in the upper, medial side of the orbit (i.e. from beside the nose) which abducts, depresses and internally rotates the eye. It is the only extraocular musc ...
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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