Looking for math words that start with R?

Math speak can be confusing at times, but it’s important to know the correct terminology if you’re to understand math problems.

To help out, for the letter R specifically, I’ve listed some of the most common math-related words:

## Math Words That Start With R

**Radical **– The √ symbol that is used to denote square root or nth roots.

**Radius **– a straight line extending from the center of a circle or sphere to the circumference or surface.

**Random **– numbers that occur in a sequence such that two conditions are met.

**Range **– the difference between the highest and lowest values in a set of numbers.

**Ratio **– an ordered pair of numbers a and b, written a / b where b does not equal 0.

**Ray **– part of a line that has a fixed starting point but does not have an endpoint.

**Real Number **– a value of a continuous quantity that can represent a distance along a line.

**Rectangle **– a 2D shape that has 4 sides, 4 corners, and 4 right angles.

**Rectangular Prism **– a 3-d solid shape that has 6 rectangular faces in which all the pairs of opposite faces are congruent.

**Recurring Decimal** – a decimal in which after a certain point a particular digit or sequence of digits repeats itself indefinitely.

**Recursive **– a type of function or expression predicating some concept or property of one or more variables.

**Reduce **– refers to the rewriting of an expression into a simpler form.

**Reflex Angle **– an angle greater than 180° and less than 360°.

**Related Facts **– basic mathematical expressions made up of three numbers.

**Remainder **– the amount “left over” after performing some computation.

**Result **– how something ended or the outcome of some action.

**Rhombus **– a quadrilateral whose four sides all have the same length.

**Right Triangle** – A triangle in which one of the interior angles is 90°

**Rigid **– the whole shape goes through the same transformation.

**Risk **– the probability of loss multiplied by the amount of loss.

**Roll **– to move or cause to move by turning over and over on a surface; The ball rolled away.

**Root **– a solution to an equation, usually expressed as a number or an algebraic formula.

**Rounding **– the process of replacing a number by another number of approximately the same value but having fewer digits.

**Row **– a number of objects arranged in a usually straight line.

**Rule Of 72** – a calculation that estimates the number of years it takes to double your money at a specified rate of return.

**Ruler **– a smooth-edged strip that is usually marked off in units and is used as a straightedge or for measuring.

I hope you found the words you were looking for from the list above.

This isn’t an exhaustive list, if there are any math words starting with the letter R that you would like added to the list, please leave me a comment below.

If you’d like to explore more math words starting with different letters of the alphabet, click any of the letters below to go to the list for that letter:

*Image credits – Photo by Joshua Hoehne on Unsplash*

Phil lives in England, UK, and has around 20 years experience as a professional life, career and executive coach. He started this blog to help others find and define their own self development journey. Blogging about a wide range of topics to help facilitate a better future.