1 (wiktionary) 2 (vi.wikipedia) 3 (en.wikipedia) 4 (glosbe)

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TOPIK 11000 KOREAN WORDS

☆☆ EXPANSION; EXTENSION; BROADENING sự mở rộng, sự nới rộng, sự phát triển, sự bành trướng ☆☆ EXTENSION; PROLONGATION sự gia hạn, sự thêm, sự tăng cường thêm ☆ SPREAD; EXTENSION sự lan truyền
HSK 3.0 11000 CHINESE WORDS
3 范围  fànwéi demesne, latitude, shot, compass, extensity, panorama, parameter, boundary, arena, stretch, territory, radius, spectrum, scope, extension, sphere, orbit, circumscription, limits, purview, grasp, extent, region, space, limit, hemisphere, horizon, envelope, bounds, realm, terrain, tether, sphere of influence, range, circuit, domain, precinct, reach, area, length, spread, bailiwick, ambit, con 6 族  zú race, nationality, ethnicity, clan, by extension, social group (e.g. office workers 上班族) 7 会诊  huì zhěn consultation (medical), to meet for diagnosis, (by extension) consultation of different specialists

ENGLISH 6000 THEME WORDS
Die Heimwerkstatt: extension cable cáp kéo dài

OXFORD 5000 CORE WORDS

extension B2 n.

TANAKA 6000 CORE WORDS