According to the "Kojien", 'shinan', composed of the 'shi' (= finger) in 'shidou' and 'nan' ( = south) means giving directions, instruction or guidance ( = 'oshiemichibiku'). A 'shinansho' is a place where it is carried out and a 'shinanyaku' is one who does it. A 'shinansha' is a vehicle used in ancient China with a compass attached and used for ascertaining directions (presumably it pointed ot the south). The only martial art where the term appears to be used is kendo. In aikido, certainly, the preferred term is 'shidou'.
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Peter Goldsbury,
Forum Administrator,
Hiroshima, Japan