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  1. Abbreviation for years before present.
    • 2004 Wikipedia article on Deluge (mythology)
      During glacial times, a stretch of level plain joined Australia with New Guinea and enabled humans to walk into Australia. That plain flooded to form the Gulf of Carpentaria, between ca 12,000 and 10,000 ybp.

Usage notes[edit]

This is a year designation alternative to the widely-used but Christian-oriented BC and AD and their secular equivalents BCE and CE. Used in historical sciences (e.g., archaeology, geology, paleontology), especially when the exact number of years is unknown (i.e., precision and current year are not significant)

Alternative forms[edit]

Derived terms[edit]

  • myBP: million years before present
  • C14YBP: Carbon-14 years before present (radiological dating)