aperiodic

American  

[ey-peer-ee-od-ik] / ˌeɪ pɪər iˈɒd ɪk /

adjective

1. not periodic; irregular.

2. Physics. of or relating to vibrations or oscillations with no apparent period.

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aperiodic British  

/ ˌeɪpɪərɪəˈdɪsɪtɪ, ˌeɪpɪərɪˈɒdɪk /

adjective

1. not periodic; not occurring at regular intervals

2. physics

   1. (of a system or instrument) being damped sufficiently to reach equilibrium without oscillation

   2. (of an oscillation or vibration) not having a regular period

   3. (of an electrical circuit) not having a measurable resonant frequency

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Other Word Forms

• aperiodically adverb
• aperiodicity noun

Etymology

Origin of aperiodic

First recorded in 1875–80; a- ⁶ + periodic ¹

Example Sentences

Slowed aperiodic activity was present in areas of the brain that contain chemicals linked with concussion symptoms like impaired concentration and memory.

From Science Daily • Nov. 27, 2024

"While it's often overlooked, aperiodic activity is important because it reflects brain cortical excitability," said study senior author Christopher T. Whitlow, M.D.,

From Science Daily • Nov. 27, 2024

For decades mathematicians have been hunting for tile shapes like these that can form only nonrepeating arrangements, called aperiodic tilings.

From Scientific American • Jul. 31, 2023

Then in March, David Smith, a hobbyist in England, and colleagues produced an aperiodic tiling using a single 13-sided shape they called a “hat.”

From Science Magazine • Jun. 7, 2023

We shall complete our enumeration of the measuring apparatus by citing Ducretet's non-oscillating galvanometer, Sir William Thomson's amperemeters, voltameters, ohmmeters, and mhosmeters, constructed and exhibited by Breguet, and a new aperiodic galvanoscope of Mr. Maiche.

From Scientific American Supplement, No. 441, June 14, 1884. by Various