Similar words
sœur
Sœur is your biological sister; belle-sœur is a sister-in-law, gained through marriage.
Similar in other languages
German
Schwägerin
Schwägerin is the German word for the same thing — both mean "sister-in-law."
Practice
1 What does belle-sœur mean?
sister-in-law
2 Fill the gap: Sa ___-sœur habite à Lyon.
Full sentence: Sa belle-sœur habite à Lyon. (His sister-in-law lives in Lyon.)
3 Which fingerprint chart matches belle-sœur?
belle-sœur: neutral register, core frequency, general domain, neutral connotation.