Base

The number an exponent is "attached" to (what a leech). For example, bⁿ has a base of b.

Coefficient

A number multiplied by a variable. In the term 23x, that'd be the number 23.

Complex Number

Any number in the form a + bi where a and b are real numbers. In English, it's a number created by the addition of one real and one imaginary number.

Domain

All the values x can take in a function. It's like x is a little king, and the domain is, well, its domain.

Exponent

The number that indicates which power to raise the base to. In the term bⁿ, the exponent is n.

Horizontal Asymptote

A way to graphically describe the end behavior for a curve that approaches (and sometimes crosses) a certain outputted y-value.

Imaginary Number

This is defined as the square root of -1.

Index

Tiny Tim-sized number sitting in the radical √. For instance, 3 in the ³√.

Irrational Number

This is a number that cannot be written as the quotient of two integers.

Radical

Also called a root, basically anything that uses √. It doesn't have anything to do with trees or plants, unless those plants are oddly mathematically inclined.

Radicand

The expression or number inside a radical.

Range

The set of all possible outputs (y-values) of the function.

Rational Number

A number that can be written as the quotient of two integers. The denominator cannot be zero.

Real Number

The set of numbers including both the rational and irrational numbers.

Simple Radical Form

An expression that's been fully reduced to prime factors and has no radicals in the denominator, or as we like to say, no radicals in the basement. Could you imagine having a radical in your basement? You'd want them out of there, too.

Vertical Asymptote

A vertical line, x = a, where f(x) approaches ± ∞ as x approaches a from the right or left.