what

The word "what" traces back to the Old English "hwæt," which was used as an interrogative pronoun and adverb. This form is derived from the Proto-Germanic "hwat," which also gave rise to similar words in other Germanic languages, such as Old Saxon "hwat," Old Norse "hvat," and Old High German "hwaz." The Proto-Germanic term originates from the Proto-Indo-European root "kwod," a neuter singular form of "*kwi-/kwo-," which was used for forming interrogative pronouns and relatives.

In Middle English, the word evolved into "what," maintaining its function as an interrogative pronoun. The shift from "hw" to "wh" in spelling reflects a broader phonetic change in the language, where the initial "hw" sound became "wh," a change that occurred around the 15th century. This transformation is part of the Great Vowel Shift and other phonological changes that marked the transition from Middle to Modern English.

Throughout its history, "what" has retained its core function of asking questions about identity, nature, or value, demonstrating the stability of its usage across centuries.