The word Wizard is often used in error by laypeople to refer to anyone who can conduct Workings. However, the term Wizard gets its proper definition in Mordechai’s A Taxonomy of Workers, Workings and Tethers.

Excerpt from A Taxonomy of Workers, Workings, and Tethers Chapter 1

To properly begin in clearing the putrid air of disorganized semantics I propose a simple yet more finite description of that common word Wizard. Nothing proves to rub against the grain of my good humor more than those who point at the Sundered Priest’s supernatural gifts and let fly the ignorance best kept within.
A Wizard is that being whose purpose for Working is the Working itself, the pursuit of the furthering of knowledge and subsequent power. He has no higher creed from god nor mortal sentient. Those he serves he does so only out of necessity or by means of acquiring that which otherwise escapes him: time, money and permission.
A Wizard bows his head only in ruse, and his mission is never completed if he is true to the Meyda and power it represents.

Most take this to mean that Wizards are those who are not born with access to a Meyda-well like the Meyda-born and Moon-touched. They are those who conduct their Workings via Meyda-circle or via self-derived Contracts with powerful entities. Such sources of Wizardly power include the Zyclest University God Stone, Dragons, and in rare cases Mordechai himself. To formulate an exhaustive list would be impossible, but the uniting thread for the moniker of Wizard is the self-mastery of power and its origin.