STD

STD
Supplemental Type Certificate
STDMA
Self-Organizing Time Division Multiple Access (VDL) ...

The transition level is where the altimeter setting is changed from STD to QNH. The layer between the transition altitude and the transition level is called transition layer.

Master caution.
A signal which indicates that one or more caution lights has been activated (from MIL-STD-1472D);
Master warning.
A signal which indicates that one or more warning lights has been activated (from MIL-STD-1472D); ...

Bus Controller: A term used to define the role of a device on a MIL-STD-1553 bus as being master.
Calibrated Airspeed: Indicated airspeed corrected for instrumentation errors, but not for air density.

See also: Flight, Aircraft, Weather, Aviation, Night