wert-
“to turn, to wind”turn, rotate, become
Root for turning, yielding Latin vertere, English -ward, worth, weird, worm.
Discussion
The Proto-Indo-European root *wert- expressed the fundamental concept of turning and rotation, a kinetic image so basic to human experience that it became one of the most productive roots in the entire family. Rix (LIV² 694) reconstructs the verb as "to turn, to wind." Latin vertere, "to turn," is the great trunk from which dozens of English words branch. Versus originally meant "a turning of the plow," then a line of writing where the pen turns back, giving English verse and the notion that poetry is language that turns upon itself. The prefixed compounds multiply without end: convertere is to turn together, hence convert; reversus is turned back, hence reverse; adversus is turned toward or against, hence adverse; universus is turned into one, hence universe. Vertīgō, the sensation of spinning, entered English as vertigo. The frequentative versāre produced versatile. Anniversary marks the year's turning back. On the Germanic side, the root produced the directional suffix *-warðaz, yielding English -ward as in toward, inward, forward — all expressing the direction in which one turns. Most remarkably, German werden, "to become," descends from this same root, embodying the metaphor that becoming is a kind of turning: to become something is to turn into it. This semantic development, from physical rotation to existential transformation, represents one of the most philosophically profound extensions in Indo-European. The root's own semantic history is itself a kind of turning.
Notes
Pokorny 1156-1160. English -ward, verse, convert, worth, weird, worm.