If something's preexisting, it was already there — it existed earlier. Someone might offer you a babysitting job, but if you have a preexisting agreement to watch your little brother that night, you'll have to turn it down.

In medicine, a "preexisting condition" is an illness or disorder that a patient has been diagnosed with in the past, often before getting new health insurance or seeing a new doctor. It was once common for US medical insurance to refuse to cover preexisting conditions, but this is no longer allowed legally. Preexist or pre-exist came first, from the "before" prefix pre- and exist, "live or be."

Definitions of preexisting
  1. adjective
    existing previously or before something
    synonyms: pre-existent, pre-existing, preexistent
    preceding in time or order
Word Family

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