Jitter

v. be nervous, be fidgety, be tense and jumpy

n. rapid variations in a signal due to electric disturbance

For other meanings of this word, see Jitter (disambiguation).Jitter is an unwanted variation of one or more signal characteristics in electronics and telecommunications. Jitter may be seen in characteristics such as the interval between successive pulses, or the amplitude, frequency, or phase of successive cycles. Jitter is a significant factor in the design of almost all communications links (e.g. USB, PCI-e, SATA, OC-48).
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Noun
1. small rapid variations in a waveform resulting from fluctuations in the voltage supply or mechanical vibrations or other sources
(hypernym) noise, interference, disturbance

Abrupt and unwanted variations of one or more signal characteristics, such as the interval between successive pulses, the amplitude of successive cycles, or the frequency or phase of successive cycles. (188 ) Note 1: Jitter must be specified in qualitative terms (e.g., amplitude, phase, pulse width or pulse position) and in quantitative terms (e.g., average, RMS, or peak-to-peak). Note 2: The low-frequency cutoff for jitter is usually specified at 1 Hz. Contrast with drift, wander.

Random variation in the timing of a signal, especially a clock.
(1995-01-16)