1861, abbreviation of cooperative. The hyphen is needed to avoid confusion with coop (n.).
Entries linking to co-op
cooperative adj.
also co-operative, "operating or striving jointly for the attaining of certain ends," c. 1600, from Late Latin cooperat-, past participle stem of cooperari "to work together" (see cooperation) + -ive. Political economy sense is from 1808, from the pre-Marx communist movement. The noun meaning "a cooperative store" is from 1883; meaning "a cooperative society" is from 1921.
coop n.
"small cage for poultry," mid-14c., coupe, from Old English cype, cypa "large wicker basket, cask," akin to Middle Dutch kupe, Swedish kupa, and all probably from Latin cupa "tub, cask," from PIE *keup- "hollow mound" (see cup (n.)).