Examples:

key in  To press keys on a calculator to enter numbers or perform operations.

key sequence  A set of instructions for performing a particular calculation or function with a calculator.

kite  A quadrilateral with exactly two pairs of adjacent congruent sides.  (A rhombus is not a kite.)

landmark  A distinguishing feature of a data set.  Landmarks include median, mode, maximum, minimum, and range.

latitude  The degree measure of an angle whose vertex is the center of the Earth and one side is a radius to the equator.  Used to indicate the location of a place with reference (north or south) to the equator.  See also longitude.

least common denominator  The least common multiple of the denominators of every fraction in a given collection of fractions.  For example, 12 is the least common denominator of 1/2, 1/3, and 1/4.  See also least common multiple.

least common multiple  The smallest number that is a multiple of two or more numbers.  For example, some common multiples of 6 and 8 are 24, 48, and 72.  24 is the least common multiple of 6 and 8.

leg of a right triangle  A side of a right triangle that is not the hypotenuse.

length  The measurement of something along its greatest dimension.

life expectancy  The number of years a typical person is likely to live.

likely  A word used to indicate the possibility of an outcome in an uncertain event.  For example, in tossing a coin, heads and tails are equally likely; in rolling two dice, some numbers (such as 7) are more likely than others (such as 2).

like terms  In an algebraic expression, either the constant terms, or any variable terms that contain the same variable or variables.  For example, 4y and 7y are like terms in 4y + 7y – z.  To combine like terms means to rewrite the sum or difference of like terms as a single term.  For example, 5a + 6a can be rewritten as 11a, because 5a + 6a = (5 + 6)a = 11a.  Similarly, 16t – 3t can be rewritten as 13t.

line  A straight path that extends infinitely in opposite directions.

line graph (broken-line graph)  A graph in which points are connected by line segments to represent data.

line of reflection (mirror line)  A line halfway between a figure (preimage) and its reflected image.

line of symmetry  A line that separates a figure into halves.  Each point in one of the halves of the figure is the same distance from this line as the corresponding point in the other half.

line plot  A sketch of data in which check marks, X’s, or self-stick notes above a number line show the frequency of each value.

line segment  A straight path joining two points, call endpoints of the line segment.  A straight path can be described as the shortest distance between two points.

line symmetry  A figure has line symmetry if a line can be drawn through that figure that divides the figure into two parts so that both parts look exactly alike, but are facing in opposite directions.

liter (L)  A metric unit of capacity, equal to the volume of a cube 10 centimeters on an edge.  1 L = 1000mL = 1000 cm3.  A liter is a little larger than a quart.  See also milliliter (mL).

logic grid  A grid of rows and columns used to organize the information in a problem.

longitude  The degree measure of how far east or west of the prime meridian a location is on Earth; determined by the angle formed by semicircles of longitude connecting the North Pole and South Pole and the prime meridian.  See also latitude.