御三時[osanji] three-o'clock snack
三鞭酒[shanpen] champagne
球面三角法[kyuumensankakuhou] spherical trigonometry
胸三寸[munesanzun] heart
元三[ganzan] New Year's period (January 1st to 3rd)

五十三次[gojuusantsugi] the 53 Toukaidou stages
向こう三軒[mukousangen] one's next three neighbors
降三世明王[gouzanzemyouou] Trailokyavijaya Vidya-raja
再三[saisan] again and again
再三再四[saisansaishi] repeatedly

遠隔講義[enkakukougi] distance learning
休講[kyuukou] lecture cancellation
公開講座[koukaikouza] extension lectures
講演[kouen] lecture
講演会[kouenkai] lecture (esp. special engagement by noted speaker)

講義[kougi] lecture
講座[kouza] academic teaching unit
講師[koushi] lecturer
講習[koushuu] short course
講習会場[koushuukaijou] training center