Armour, particularly the old style suit of armour, signifies chivalry, protection and the need to protect or be protected.
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Armour, Helmet Etc. Armour, coat of mail*helmet, shield, flag etc, is seen in the dream means protection just as protection is sought through forts and shields. Also, victory, superiority and power will be acquired.(*A suit of armour made of linked metal rings or overlapping plates.)