Sinus totus

In trigonometry, the sinus totus (Latin for "total sine") was historically the radius of the base circle used to construct a sine table; that is, the maximum possible value of the sine.

Letting the notation $$\operatorname{Sin} \theta$$ stand for the historical sine, and $$\sin \theta$$ stand for the modern sine function,
 * $$\operatorname{Sin} \theta = R \sin \theta,$$

where $$R$$ is the sinus totus, $$R = \operatorname{Sin} 90^\circ.$$