The answer depends upon what we mean by “the first word.”
There was no single first word for Witch used throughout the world. Many cultures had their own words for people believed to practice magic, divination, healing or harmful sorcery. If we are asking about the origin of the English word witch, however, its earliest known ancestors are the Old English words wicca and wicce.
Old English used wicca for a male practitioner and wicce for a female practitioner. These words eventually passed through the Middle English wicche and developed into our modern word witch. One of the earliest surviving written examples appears in the Laws of King Alfred, dating from around 890. The Oxford English Dictionary identifies witch as a word inherited from Germanic and confirms that it was in use during the Old English period. Oxford English Dictionary
It is often said that wicca or wicce meant “wise one” or “one who seeks wisdom.” This is a beautiful interpretation, and many modern Witches embrace the description “Craft of the Wise.” Unfortunately, it is not a firmly supported translation. Old English sources use the words for people associated with magic, sorcery, divination or enchantment, but the deeper origin of the words remains uncertain. Even etymologists do not agree on precisely what wicca and wicce meant before they appeared in surviving written records. Oxford University Press
The word wizard does have a clearer connection to wisdom. It comes from the Middle English wysard, built from a word meaning “wise.” Its earliest meaning was closer to “wise man,” philosopher or sage; its specific association with magical power developed later. Witch and wizard therefore came to occupy similar territory, but they do not come from the same word root. Oxford English Dictionary
Modern Wicca, pronounced “WICK-uh,” takes its name from these Old English words, but it should not be confused with their original usage. Wicca is the name of a modern Pagan religion whose public development is particularly associated with Gerald Gardner in the twentieth century. The similarity in spelling does not demonstrate that the Old English wicca practiced the religion now called Wicca.
Nor did the word witch suddenly become negative because of the Malleus Maleficarum. The Old English law mentioning wiccan already treated them as dangerous and prohibited practitioners. Associations between magic, wrongdoing and spiritual danger therefore existed centuries before the Malleus.
The Malleus Maleficarum, usually translated as The Hammer of Witches, was published in 1486. It did not invent the hostile image of the Witch, but it helped spread the claim that witchcraft involved heresy, harmful sorcery and cooperation with the Devil. It was also fiercely misogynistic and argued that women were especially vulnerable to demonic influence. Washington University Libraries
Women made up the majority of those accused during the European witch trials, although men were also accused and the balance varied considerably from one country and region to another. This history leads us to another complicated word: warlock. It comes from an Old English word associated with a traitor, deceiver or oath-breaker and only later came to mean a male Witch in Scots usage.
The history of the word witch, then, is not a simple journey from “wise person” to “evil sorceress.” It is a complicated history shaped by language, law, religion, fear, and gender.