Definition

1. Noun:
   • The vertical axis in a plane coordinate system: In a two-dimensional Cartesian coordinate system, the y-axis is the vertical line, typically used to represent the dependent variable or the second coordinate in an ordered pair (x, y). It is perpendicular to the horizontal x-axis.

Usage

• The is used to define the vertical dimension on a graph or chart.
• In an ordered pair (x, y), the second number (y) corresponds to a position along the .
• It is a fundamental concept in mathematics, physics, engineering, and data visualization.

Examples

• Noun:
  • The point (3, 5) is located 3 units along the x-axis and 5 units up the y-axis.
  • On this graph, time is plotted on the x-axis and temperature is plotted on the y-axis.
  • To find the intercept, look at where the line crosses the y-axis.

Advanced Usage

• "y-axis intercept": The point where a line or curve crosses the . This occurs when the x-coordinate is zero.
  • The equation's constant term gives the y-axis intercept.
• "Reflection across the y-axis": A transformation where each point (x, y) on a graph is mapped to its mirror image (-x, y) across the .*
  • The function is symmetric with respect to the y-axis.

Variants and Related Words

• Axis (n): A reference line in a coordinate system.
• X-axis (n): The horizontal axis in a plane coordinate system.
• Z-axis (n): The third axis in a three-dimensional coordinate system.
• Ordinate (n): The y-coordinate of a point; its distance from the x-axis, measured parallel to the .

Synonyms

• Vertical axis: A descriptive synonym emphasizing its orientation.
• Ordinate axis: A less common synonym relating to the coordinate.

Related Phrases

• Label the y-axis: To write a description (like "Height in cm") next to the on a graph.
  • Remember to label the y-axis clearly on your chart.
• Scale of the y-axis: The range and interval of values represented along the .
  • The scale of the y-axis goes from 0 to 100 in increments of 10.

Noun

1. the vertical axis in a plane coordinate system