IPA: /ˌkrɪp.təˈdʒɛn.ɪk/
KK: /ˌkrɪp.təˈdʒɛn.ɪk/
Relating to something that has an unclear or unknown origin, often used to describe diseases.
The doctors were puzzled by the cryptogenic condition that had no clear cause.
Cryptogenic → It is formed from "crypto-" (from Greek "kryptos", meaning hidden or secret) and "genic" (from Greek "genes", meaning born of or produced by). The word "cryptogenic" refers to something that is produced by hidden or unknown causes.
Think of something that is 'hidden' ('crypto-') and 'produced' ('genic') — that's why cryptogenic refers to something with unknown origins.