The Hakama (the traditional garb for Aikido students) and Its Meaning
O Sensei lectured his uchi deshi on the meaning of the seven pleats of the hakama on an occasion when Mitsugi Saotome forgot to bring his hakama to class.
“They symbolize the seven virtures of budo,” O Sensei said. “These are jin (benevolence/goodness), gi (honor or justice), rei (courtesy and etiquette), chi (wisdom & intelligence), shin (sincerity), chu (loyalty), and koh (piety/devoutness). We find these qualities in the distinguished samurai of the past. The hakama prompts us to reflect on the nature of true bushido. Wearing it symbolizes traditions that have been passed down to us from generation to generation. Aikido is born of the bushido spirit of Japan, and in our practice we must strive to polish the seven traditional virtues.” — (from The Principles of Aikido by Mitsugi Saotome)
Learn more here http://www.aikidofaq.com/misc/hakama.html