Dropout may refer to:

Education

• A student who quits school before graduation.
  • List of high school dropouts
  • List of college dropouts

Telecommunication

• A momentary loss of signal in a communications system. This is usually caused by noise, propagation anomalies, or system malfunctions.
• A failure to properly read a binary character from data storage. This is usually caused by a defect in the storage medium or by a malfunction of the read mechanism.
• In magnetic tape, disk, card, or drum systems, a recorded signal with an amplitude less than a predetermined percentage of a reference signal.

Electrical engineering

• The potential difference between the input and output terminals of a linear regulator, below which the regulator can not meet its specifications

Cycling

• Dropout (bicycle part), a bicycle part

Astronomy

• Dropout (astronomy), a radiation source whose radiation intensity falls off sharply above a specific wavelength

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