I am guessing you are refering to the trigonometric Soh Cah Toa.
This a way people use to remember sine cosine and tangent.
Soh-Sine=$${\frac{{\mathtt{opposite}}}{{\mathtt{hypotenuse}}}}$$
Cah-Cosine=$${\frac{{\mathtt{adjacent}}}{{\mathtt{hypotenuse}}}}$$
Toa-Tangent=$${\frac{{\mathtt{opposite}}}{{\mathtt{adjacent}}}}$$