yearthe

Yearthe is a fictional time unit used in worldbuilding and speculative fiction to denote a complete cycle of seasons within a planetary year. In most depictions, a yearthe corresponds to one solar year, roughly 365 days, though some variants fix it at exactly 365 days to avoid leap-year irregularities.

The term is drawn from a constructed language used in the Yearthe setting, combining elements that scholars translate as "year" and "turn" or "cycle." The earliest published uses appear in mid-20th-century worldbuilding compendia and later in novels and role-playing materials.

In-world, yearthe calendars commonly begin their year at the vernal equinox and divide the year into twelve or thirteen months named after seasonal motifs. Weeks typically run seven days, and occasional intercalary days or weeks are inserted to keep the calendar aligned with the seasons.

Culturally, yearthe is tied to agriculture, ritual calendars, and public administration. Dates are recorded in terms of yearthe counts since a fixed epoch, and major festivals align with solstices and equinoxes. In storytelling, the term helps anchor events in a familiar, tangible cadence.

As a concept, yearthe illustrates how fictional calendars provide rhythm and texture to worldbuilding, offering a plausible framework for chronology, property records, and historical narratives.