C2 is near-native. Vocabulary work is about precision, connotation, and idiom, not basic meaning.
Years of immersion plus deliberate study.
C2 is near-native. The active vocabulary is 16,000+ words, but the work isn't about adding more; it's about precision, connotation, and idiom. You learn that prevaricate isn't a synonym for lie, that bask and wallow take different objects, and that the order of adjectives in English isn't a matter of taste. Subtle register shifts (formal/informal, written/spoken, regional) become deliberate choices.
If you can read poetry, write a publishable essay, and pass for a long-term resident in conversation, you're around C2. Reaching C2 typically requires years of immersion plus deliberate study. Only a small fraction of IELTS candidates score Band 9 (the C2 equivalent), and most native speakers don't actually pass C2 exams without preparation.
At C2 there's no shortcut to volume. Read literary fiction, academic texts, and broadsheet journalism. Pay attention to what feels off when you write; that's usually a register or collocation gap. Use spaced repetition for rare words and idioms you want to add to active vocabulary. The work at this level is endless and incremental; vocabulary growth doesn't stop, it just becomes invisible.