The Math Forum

Ask Dr. Math

Middle School Archive

Dr. Math Home || Elementary || Middle School || High School || College || Dr. Math FAQ

This page:
  definitions checkmark

  Dr. Math

See also the
Internet Library:


About Math

   factoring expressions
   graphing equations

   factoring numbers


     conic sections/
   3D and higher



Number Sense
   factoring numbers
   negative numbers
   prime numbers
   square roots

Word Problems

Browse Middle School Definitions

Stars indicate particularly interesting answers or good places to begin browsing.

Factors and Multiples [01/27/1998]
My son is in 4th grade and needs help naming a common multiple of a pair of numbers.

Flips, Reflections, Rotation, and Quadrants [11/10/1998]
These terms are being used to describe the movement of shapes. What do they really stand for?

The Fourth Dimension [8/24/1995]
What is the fourth dimension mathematically?

Fraction Multiplication [7/22/1996]
The meaning of the dot between two fractions.

Golden Triangle: An Isosceles Triangle [01/23/2001]
What is the Golden Triangle?

Golden Triangle: What is It? [09/19/1999]
What is a Golden Triangle?

Grad as a Measure of an Angle [03/20/2002]
I would like to know about the origins, use in the past, and whether (and how) the grad is used now.

Greater/Less Than Signs [04/09/1997]
I always get my greater and less than signs mixed up. Which is which?

Greater Than and Less Than Symbols [05/30/2000]
What does it mean when a greater than or less than symbol appears before a number, with nothing to the left of the symbol?

Grouping Symbols [08/27/1998]
I need the names of four grouping symbols. I already know of parentheses and brackets so that takes care of two...

Harmonic Mean [12/15/1996]
What is the harmonic mean and how do you use it?

Hexagon vs. Hexagram [01/11/1999]
What is the difference between a hexagon and a hexagram?

Histogram [04/16/2001]
What is a histogram? What makes a histogram good?

Historical Dozen [03/19/2002]
Why do we ship products in quantities of 12?

History of Abscissa [03/26/2001]
Where does the word abscissa come from?

History of the Word [08/21/2006]
Why is a ruler called a ruler?

History of the Word 'Exponent' [11/26/2003]
Who came up with the name 'exponent'?

'Honest' Numbers [11/11/2002]
My teacher asked the class: What is the only 'honest' number?

How Fast is a Knot? [12/21/1995]
Ships travel in knots (which is a speed). How fast is a knot?

How the Trig Functions Got their Names [12/14/1997]
I can guess why three of the trig functions are called cosine, cotangent, and cosecant. But why were the other three named the sine, the tangent, and the secant?

Identifying Algebraic Properties [12/29/1996]
How do you identify which algebraic property has been used in each step of a simplification process?

Identity and Inverse Properties for Zero [01/07/2004]
If we subtract 0 from a number and get the same number, doesn't that make 0 an identity for subtraction? Also, can't a number be its own inverse for subtraction?

Incenter, Orthocenter, Circumcenter, Centroid [01/05/1997]
I have been having trouble finding the Euler line of a triangle.

Inclusive and Exclusive Definitions [04/05/2001]
Are squares rectangles? Are rectangles squares?

Inclusive vs. Exclusive Definitions [01/24/2002]
My geometry teacher says that a square is not also a rhombus, a rectangle, and a parallelogram. Please help!

Interpreting the Difference Between Two Numbers [09/22/2006]
If a question asks "What is the difference between 15 and 12" or "What is the difference between 12 and 15," would your responses be +3 and -3 respectively? Or would they both be +3?

Intersection of Circles [10/08/1998]
I do not understand the term intersection in geometry.

Introduction to Quadrants in the Coordinate Plane [02/05/2004]
What is a quadrant? How do you find it? I had to identify 9 ordered pairs on a graph. Now I need to also name the quadrant each one is in.

Is a Circle a Polygon? [03/07/1999]
A circle is not a polygon.

Is an Equilateral Triangle Also Isosceles? [02/19/2008]
Can equilateral triangles also be classified as isosceles? In other words, does an isosceles triangle have exactly two equal sides or at least two equal sides?

Is a Square a Rectangle? [06/04/1997]
Are squares rectangles? What is a pentagon?

Is Kite the True Name? [03/29/2002]
Is kite the true math name for this shape, or is there another?

Is the Fraction N/N Considered Proper or Improper? [10/31/2003]
If a fraction has an equal numerator and denominator, what is it called? Is it proper, improper, or something else?

Is Zero Really a Number or Just a Concept? [09/15/2005]
I've been taught that infinity is just a concept, not an actual number. I'm wondering if the same thing can be said of zero?

K as an Abbreviation for Thousands [05/29/2002]
I was taught that 30K meant thirty thousand. Is that correct?

Larger Than and As Large As [08/01/1999]
If the percussion section has 6 people, does the expression "the brass section is three times larger than the percussion section" mean that the brass section is 3*6 = 18 people or 4*6 = 24 people?

Latin Origins of Trig Functions [11/20/1998]
What are the etymologies of the six trigonometric functions: sine, cosine, tangent, cosecant, secant, and cotangent?

Least Common Multiple with Zero [03/26/2003]
I'm trying to find any reference about the least common multiple of two numbers when one (or both) is zero.

Left Angles [06/01/1999]
What is a left angle?

Leg of a Triangle [04/02/2002]
I need to know where the name "leg" of a triangle comes from, or what its origin is.

Page: [<prev]  1  2  3  4  5  6  7  8  9 10 [next>]

Search the Dr. Math Library:

Search: entire archive just Middle School Definitions

Find items containing (put spaces between keywords):
Click only once for faster results:

[ Choose "whole words" when searching for a word like age.]

all keywords, in any order at least one, that exact phrase
parts of words whole words

[Privacy Policy] [Terms of Use]

Home || The Math Library || Quick Reference || Search || Help 

© 1994- The Math Forum at NCTM. All rights reserved.