One of the mysteries of the English language finally explained.
Any of various organizations of girls or women, formed for the purpose of mutual support, spiritual instruction, or service to the community; (now chiefly) specifically a Christian organization of this type, first established in Dublin, Ireland in 1893.
Late 19th century; earliest use found in The Manitoba Free Press. From the genitive plural of girl + brigade, after Boys' Brigade.
Girls' Brigade/ˈɡəːlz brɪˌɡeɪd/
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