This is a potential security issue, you are being redirected to https://csrc.nist.gov.
An inherent characteristic of an oscillator that determines how well it can produce the same frequency over a given time interval. Stability does not indicate whether the frequency is right or wrong, but only whether it stays the same. The stability of an oscillator does not necessarily change when the frequency offset changes. An oscillator can be adjusted, and its frequency moved either further away from or closer to its nominal frequency without changing its stability at all.
The stability of an oscillator is usually specified by a statistic, such as the Allan deviation, that estimates the frequency fluctuations of the device over a given time interval. Some devices, such as an OCXO [Oven Controlled Crystal (Xtal) Oscillator] have good short-term stability and poor long-term stability. Other devices, such as a GPS disciplined oscillator (GPSDO), typically have poor short-term stability and good long-term stability.
NISTIR 8323 from NIST T&F Glossary - Adapted