光盘（等于optical disc，laser disc）

laser disk \laser disk\ n.
A digital data storage medium consisting of a thin disk onto
which the data is impressed by a laser, in the form of a
linear sequence of dots; same as {optical disk}. The data is
subsequently read back by the use of a laser beam. See also
{compact disk}.

Note: The original disk may be created by use of a laser, but
copies of the original disk may be created by a
replicating process which does not itself require a
laser.
[PJC]