IPA: /ˌɔːtəˈmætɪkli/
KK: /ɔːtəˈmætɪkli/
In a way that happens without needing any human action or intervention.
The doors open automatically when you approach them.
Automatically → It is formed from "auto-" (from Greek "autos", meaning self) and "-matically" (from Greek "matikos", meaning of or relating to a process). The word "automatically" means to do something by itself or through a process without human intervention.
Think of 'self' ('auto-') doing something through a process ('-matically') — that's why automatically means something happens by itself.