[kal-si-don, kal-seed-n]
  1. an ancient city in NW Asia Minor, on the Bosporus, opposite Byzantium.
  2. Council of, the ecumenical council held there in a.d. 451.
Related formsChal·ce·do·ni·an [kal-si-doh-nee-uh n] /ˌkæl sɪˈdoʊ ni ən/, adjective, noun Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for chalcedon

Historical Examples of chalcedon