Lewis & Short

thesmŏphŏrĭa, ōrum, n., = θεσμοφόρια, τά, the festival of Demeter or Ceres (as lawgiver) among the Greeks, Plin. 24, 9, 38, § 59; Arn. 5, 173; Macr. S. 3, 12; Hyg. Fab. 147.