Glossary

A to F

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ANNUAL

annual

For one year. The family bought an annual membership to the zoo.

BILLION

billion

A billion is one thousand millions. It is written as 1 followed by nine zeroes: 1,000,000,000. In 2020,
the world’s population was nearly 8
billion people.

BIODIVERSITY

biodiversity

The variety of plant and animal life in a particular place. Biodiversity is nature’s way of keeping things in balance.

CENSUS

census

An official count of people or things in an area. The U.S. Census is taken every ten years.

BROAD-LEAVED TREES

broad-leaved trees

A family of trees with wide, flat leaves. Oaks and maples are two examples. In cold climates, most broad-leaved trees lose their leaves in fall.

CALCULATE

calculate

To determine the exact number or amount of something using math

CIRCLE

circle

A closed line that curves around a central point. Every point on the edge of a circle is the same distance from the center.

CONIFERS

conifers

A family of trees that have long, thin leaves called needles and produce seed-filled cones. Pines and cedars are two examples. Many conifers keep their leaves all year round.

CONTINENT

continent

One of the seven large land
masses on the earth. The seven continents are Asia, Africa,
Europe, North America, South America, Australia, and Antarctica.

DATA

data

Information or facts gathered by counting, measuring, questioning, or observing. Data are usually communicated with numbers.

DECREASE

decrease

(verb) To become smaller in size or number

DESERT

desert

An area of land where very little rain falls. Often sandy with few plants or trees.

ESTIMATE

estimate

(verb) To make a rough guess about the number or amount of something. (noun) A rough guess about an amount, size, cost, etc.

FLIP

flip

When you flip a shape, you turn it over and see its mirror image.

FOOT

foot

A unit for measuring height, length, and distance. One foot equals 12 inches and about 30 centimeters.

BAR GRAPH

bar graph

A graph that uses rectangular bars to show how large each value is. A bar graph can have vertical or horizontal bars.

FREQUENCY

frequency

The number of times a response occurs in a data set

FUNGI

fungi

Living things that release nutrients into the soil by breaking down fallen leaves and dead trees. Mushrooms and molds are examples of fungi.