IPA: /ˌɪn.təˈsɪs.təm/
KK: /ɪnˈtɜrˌsɪstəm/
Relating to or occurring between different systems.
The intersystem communication allows devices from different manufacturers to work together.
Intersystem → It is formed from "inter-" (meaning between) and "system" (from Greek "systēma", meaning a whole made up of parts). The word "intersystem" refers to something that exists or occurs between different systems.
Think of things that exist 'between' ('inter-') different 'systems' — that's what intersystem means.
No commonly confused words.