pre-existing BrE AmE , pre·ex·ist·ing /ˌpriːɪɡˈzɪstɪŋ◂/ adjective [only before noun]
[ Word Family: noun : ↑ existence ≠ ↑ non-existence , ↑ existent , ↑ existentialism , ↑ existentialist , ↑ coexistence ; adjective : ↑ existent ≠ ↑ nonexistent , ↑ existing , ↑ pre-existing , ↑ existential , ↑ existentialist ; verb : ↑ exist , ↑ coexist ]
formal existing before a particular time or event:
Inform your doctor of any pre-existing medical condition.