1. equipment that records information about the performance of an aircraft during flight
The Collaborative International Dictionary of English v.0.48:
Black box \Black" box`\ (bl[a^]k"b[o^]ks`), n.
1. any electronic instrument or part of an instrument whose
function is defined, but which is treated as a unit
without consideration of the internal mechanisms; broadly,
any device whose internal workings are considered as
incomprehensible or mysterious by the user; as, to treat
the meter as a black box and take its readings on faith.
2. (aviation) a device which maintains a record of cockpit
conversations and the readings of many of the instruments
on board an aircraft, continuously or at frequent time
intervals during a flight. It is of rugged design to
withstand a violent crash, and is used to determine the
causes of aircraft accidents.
Note: They are often brightly colored to assist recovery, not
WordNet (r) 3.0 (2006):
n 1: equipment that records information about the performance of
an aircraft during flight
The Free On-line Dictionary of Computing (18 March 2015):
An abstraction of a device or system in which only
its externally visible behaviour is considered and not its
implementation or "inner workings".
See also functional testing.