Let's start with the beginning.
Definition/Form - the anchor of all existence. Used to limit Possibility into Reality. Not the word 'definition' with a lower case 'd' used to limit the possible meanings of a verbal sound or assembly of drawings. Will Defines Reality.
Will - the force that Defines Possibilities and Realities; only Souls have a Will. Will is the consciousness of the Soul.
Soul - a piece of True Divinity? The Void? Maybe the Void is True Divinity. Unknown. It is the source of Possibility in Reality, and thus the base from which Will stems.
Sentient - has a soul.
Void - this is the Undefinable. It is nonexistence itself, and only thus perceived leads to existence from the Void. The metaphor used to perceive it is the relationship darkness has to light. Because darkness exists, light can be defined.
Possibility/Chaos - Undefined existence. This cannot be part of Reality, though Reality might dissolve into Chaos and the Void. Creatures that tap into Chaos for unlimited power constantly face the danger of becoming Undefined, thus slipping from Reality and possibly becoming one with the Void.
Mana/Qi/Power/Energy/Magic - all refer to partially Defined Possibility. The Definitions limit the possibilities enough for Reality to incorporate it without falling apart, but these can and do change Reality either by being used to alter a Definition (Alteration), strengthen a Definition (Reinforcement), destroy a Definition (Destruction), or be Defined further into Reality (Conjuration).
Reality - when Possibility is fully Defined by Will, it becomes Reality.
True Divinity - the actual God who is omnipotent and omniscient, who creates and controls all. No actual Definition known.
Godhood - with a lower case 'g'. Refers to a being that is no longer Defined by the Will of another, but is Defined by its own Will. While nigh immortal, it is still possible to destroy a god with powerful enough magic or the right exploitation of a weakness, which is why most gods seek to resolve any inner conflict before Ascension.
Ascension - The process of switching the Will Defining oneself to one's own Will. The process endangers the existence of the being undergoing Ascension, especially if done too fast. There are multiple forms of Acension and cultivation, see Appendix B.
Cultivation - the act of assimilating power or other mostly unDefined Possibility so as to form a new base for your existence with your Will. This process may or may not be assisted or hampered by a World's Laws.
Space - definition of Definition. Space is Reality Defined, part of the cause and effect system of Reality. Something that is more self Defined may take up less to no space, such as a god.
Sleep - the time when one's Will is withdrawn from the world. It fully reconnects with Soul, but stays connected to the body. At this time, any sentience or subconscious that is the body's becomes more active, as it is no longer repressed by the Soul.. In very rare cases, this consciousness may have its own Will and may be even more proficient than the Soul's Will. In these cases, it is probably because there is a second Soul attached to the body.
Body - the vehicle of consciousness. Bodies are medium through which a Will affects the world. Complicated bodies, e.g. biological, allow for a greater separation between Will and Reality, as the Will is more caught up in affecting the body. Simple bodies, such as ghosts, decrease this distraction, allowing Will to affect Reality much more easily. However, this in turn this allows Will to be affected much more easily by more Defined objects. Ghosts tend to be bound in place, and are weak to magic that affects their Definition in any way. Additionally, certain physical objects may harm them, depending on the world's Laws.
World Law - rule by which the a world operates, as Defined by the Will that created the world
Plane - a separate world connected to another, usually created by the same Will
Alignment - refers to innate suitability and understanding of a mana Concept/Element, and is based solely on Definition