Aura

Aura refers to a number of things, which overlap in the minds of others to mean area of effect, centered on the caster. 
# The natural reach of your soul, and the furthest you can manipulate Aether without a dedicated technique.
# A cloak of spiritual energy which hangs upon the skin of the user which may or may not have physical effects. 
# The feeling given off by a magic user, which is often used to suppress others. 
# An area of effect spell which moves with the user.
Chi Aura - extending personal chi from the meridian nodes to create an aura of life energy. With training, a chi arua can extend beyond the soul's reach, but when not in actively focused upon, the aura will either snap back to the soul-aura or dissipate into the environment. 
Psychic Aura - broadcast from the sixth or seventh chakra, psychic aura has no range limit, but also no resting state. 
Soul Aura - or simply aura, is the furthest natural reach of a soul, and what is most commonly being referenced when talking about aura.
Aura Suppression - Aura is the reach of your soul, but that doesn't mean you have to be stretching all of the time. Pulling back in has a number of uses. Focusing ones power for strength or control, hiding from the spiritual sight of others and reducing one's impact on the world.
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Suppression Aura - before or without gaining control of ones aura, souls will often use this field to communicate emotions or intent to one another. One expression of this that is considered particularly useful in honor based cultures is the ability to leverage this interaction to express displeasure or dominance upon others within your range. 
Casting via Aura - While most magic users cast via their hands for ease of visualization, magic is independent of the flesh, and therefore can be cast from any point on the spiritual body. As the aura is the representation of the the spirits reach, this means a properly trained player can cast from any point within their aura as though it were their hand.
Folded Aura - a change of perspective on a spiritual level allows the trained to store an object from the physical world within the spiritual world, with the soul essentially holding onto it.