WINDOWEDÜ

adjective (Business World) Of the security thread in a banknote: woven into the paper so that it is visible only in short stretches. Etymology: A figurative use of windowed, alluding to the fact that the thread is partially embedded and partially visible. History and Usage: Windowed threads were introduced in Bank of England notes in the mid eighties. It is...the only means of incorporating security threads in the 'windowed' form which has become a feature of Bank of England ø20 and ø10 notes in recent years. New Scientist 3 Dec. 1988, p. 84