1ky

1ky is an informal shorthand for one kiloyear, a unit of time equal to 1,000 years. In scholarly writing, more common abbreviations are ky (kiloyear), kyr, or ka (kiloannum). The exact form depends on field and publication; the unspaced form "1ky" appears mainly in datasets or informal notes and is not widely standardized.

Kiloyears are used to describe long timescales in geology, paleoclimatology, archaeology, and related disciplines. For example, 3 ky equals 3,000 years, and 12 kyr equals 12,000 years. When expressing dates with respect to present, researchers may write "ky BP" or "kyr BP," indicating years before present, with present defined as 1950 CE in radiocarbon dating. The term helps compare ancient events with modern history and is commonly used for ranges from a few thousand to tens of thousands of years. For precision in formal contexts, some authors prefer ka (kiloannum) to avoid potential confusion associated with different uses of "ky."