deltayankee;
Good guess, but in those days codewords were usually selected at random from a list and codewords that might hint at their meaning were discouraged.
Not entirely correct. In fact, entirely wrong.
Rainbow codes were not introduced until
after the war so
RESponsor (?) and
INterrogator may well be valid.
The Rainbow Codes were a series of code names used to disguise the nature of various British military research projects from after the Second World War until 1958 when they were replaced by an alphanumeric code system. The Ministry of Supply (MoS) initiated the idea since during the war some German secret projects could be inferred from their code names; for example, that a radio navigation device "Wotan" used a single beam because the Germanic god Wotan was one-eyed.
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