# Vocabulary Words

### By: Hannah Popp

**Radians: an angle made at the center of the circle by an arc whose length is the same as the radius.**

**Degrees: a measure of angles **

**Initial side: The ray where measurements of an angle starts.**

*Terminal Side: The ray where measurements of an angle stops.*

**Coterminal Angle: Angles which share a terminal side**

**Reference Angle: Is the smallest angle between the terminal side and the x-axis **

**Unit Circle: Circle with a radius of 1**

**Trig Ratios: Functions used to calculate the missing length of a triangle**