IPA: /ˌæntɪˈdroʊmɪk/
KK: /æntɪˈdroʊmɪk/
Moving or occurring in the opposite direction from what is usual or expected.
The antidromic flow of the river surprised the scientists studying its patterns.
Antidromic is formed from "anti-" (meaning against) and "dromos" (from Greek, meaning running or course). The term describes a movement or action that runs counter to a normal or expected direction.
Think of 'anti-' meaning against and 'dromos' meaning running — this helps you remember that 'antidromic' refers to something that runs against the usual direction.