IPA: /ˌɛkstrəˈlɛɡəli/
KK: /ˌɛkstrəˈlɛgəli/
In a way that is not allowed by the law; acting outside legal boundaries.
The organization operated extralegally, ignoring the regulations set by the government.
Extralegally → It is formed from "extra-" (meaning outside) and "legal" (from Latin "legalis", meaning lawful). The word "extralegally" means in a manner that is outside the law or not legally sanctioned.
Think of 'extra' meaning 'outside' and 'legal' meaning 'lawful' — so extralegally refers to actions taken outside the bounds of the law.
No commonly confused words.