, literally meaning 'banner', had a more specific meaning on the battlefields of feudal
Japan. It referred to a particular type of banner denoting units within an army; nobori became much more common in the
Sengoku period, coming into use alongside the earlier
hata-jirushi. They were long, narrow flags, attached to a pole with a cross-rod to hold the fabric straight out and prevent it from furling around the rod; this way, the flag would always remain visible and identifiable.
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Colorful banners with rikishi names written on them displayed outside the Sumo venue