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

Core Words Familarize yourself with the 'core words'.
Compounds Expand your vocabulary by studying more complex words built by the 'core words'.
Wordsense Learn about the wordsenses of the english term.

ETYMOLOGY

KOREAN 3.0 Eng Wordtype Etym. Gb Vie
☆☆☆ LONELY; SOLITARY Adjective 孤单，孤独 cô độc, đơn độc
☆☆ LONESOME; SOLITARY; CHEERLESS Adjective 孤寂，落寞 đơn độc, cô quạnh