Double sideband transmission (DSB)
That method of operation in which both bands of frequency, produced by the process of modulation, are transmitted equally.
Reference: I.E.C. (modified)
Please note that this is the term as it stands in the original IALA Dictionary edition (1970-1989)
Celsius (previously Centigrade)
International Association of Marine Aids to Navigation and Lighthouse Authorities - AISM