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imaginary axis

American  
[ih-maj-uh-ner-ee ak-sis] / ɪˈmædʒ əˌnɛr i ˈæk sɪs /

noun

Mathematics.
  1. the vertical axis in an Argand diagram.


Etymology

Origin of imaginary axis

First recorded in 1700–05

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Complex here doesn’t mean complicated but refers to the complex plane, a two-dimensional plane with a real axis and an imaginary axis, where complex numbers like 2+3i live.

From Scientific American

Decades ago, astronomers noticed the lopsided heart was almost exactly on the opposite side of the imaginary axis line that connects Pluto to its moon Charon, but they didn’t know why.

From The Wall Street Journal

The study, which was published in March in Cognitive Science, shows that along with the slope they had previously identified running “uphill” away from the door, a second imaginary axis runs from the central fireplace “uphill” to the side walls.

From National Geographic

Standing more than 45 feet high and carved from a single piece of granite, it features 121 human figures — men, women, children and babies, pivoting around an imaginary axis in a tangle of torsos and limbs.

From Washington Post

“Yes,” said Uncle Henry, “and it spins so steadily in that slanting position that the north end of its imaginary axis always points toward the same place, a point very close to the north star, or Polaris as it is called.”

From Project Gutenberg