g
The abbreviation for gram, a metric unit of mass. In physics, g also stands for the acceleration due to gravity.
Gallon
A US customary unit of liquid capacity equal to 4 quarts, or about 3.785 liters.
GCF
Short for greatest common factor: the largest number that divides evenly into two or more numbers.
Geometric mean
The nth root of the product of n numbers. The geometric mean of 4 and 9 is √(4 × 9) = 6.
Geometric probability
Probability found by comparing lengths, areas or volumes, such as the chance a random point in a square lands inside a circle.
Geometric sequence
A sequence in which each term is found by multiplying the previous term by the same number, the common ratio.
Geometric series
The sum of the terms of a geometric sequence.
Geometry
The branch of mathematics that studies the size, shape and position of points, lines, angles, surfaces and solids.
Glide reflection
A transformation that combines a reflection across a line with a translation along that line, like a trail of footprints.
Golden ratio
The ratio, about 1.618 and written φ, that results when a line is divided so the whole is to the longer part as the longer part is to the shorter.
Golden rectangle
A rectangle whose sides are in the golden ratio. Cutting off a square leaves a smaller golden rectangle.
Googol
The number 1 followed by 100 zeros, or 10¹⁰⁰.
Gradient
The steepness of a line, found as rise over run; another word for slope.
Gram
A metric unit of mass. A paper clip has a mass of about 1 gram, and 1000 grams make a kilogram.
Graph
A visual display of data or of the relationship between variables, often drawn on a coordinate plane.
Graph paper
Paper printed with a grid of small, evenly spaced squares, used for drawing graphs, shapes and diagrams accurately.
Great circle
The largest circle that can be drawn on a sphere. Its center is the center of the sphere, like the equator on a globe.
Greater than
Larger in value than, written with the symbol >. For example, 9 > 5.
Greater than or equal to
At least as large as, written with the symbol ≥. x ≥ 3 includes 3 and every number above it.
Greatest common divisor
Another name for the greatest common factor: the largest number that divides two or more numbers evenly, often used to simplify fractions.
Greatest common factor
The largest factor that two or more numbers share. The greatest common factor of 12 and 18 is 6.
Greatest integer function
The function ⌊x⌋ that gives the greatest integer less than or equal to x, such as ⌊2.7⌋ = 2; also called the floor function.
Grid
A pattern of equally spaced horizontal and vertical lines that cross at right angles to form squares or rectangles.
Gross
A group of 144, or 12 dozen.
Grouping symbols
Parentheses ( ), brackets [ ] and braces { } that show which operations to do first.
Growth factor
In exponential growth, the number greater than 1 that a quantity is multiplied by in each period. A 5% increase has a growth factor of 1.05.