# Scientists Say: Y-axis

## This little line can tell you a lot about what is on your graph

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**Y-axis **(noun, “Why AXE-iss”)

A vertical line on a graph. It can be located to the right or left, or even in the middle. Scientists label the y-axis with whatever they are measuring. Perhaps it is time, or a population, or grams of a substance. The y-axis and its horizontal partner, the x-axis, tell us what data presented in the graph represents.

**In a sentence **

When trying to float a candy bar, my graph of the results showed the mass of the candy on the y-axis.

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**Power Words**

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**axis **The line about which something rotates. On a wheel, the axis would go straight through the center and stick out on either side. (in mathematics) An axis is a line to the side or bottom of a graph; it is labeled to explain the graph’s meaning and the units of measurement.

**x-axis **(in mathematics) The horizontal line at the bottom of a graph, which can be labeled to give information about what the graph represents.

**y-axis** (in mathematics) The vertical line to the left or right of a graph, which can be labeled to give information about what the graph represents.