Bithyn-ia
a Roman province of Asia Minor. Mentioned only in Ac 16:7 and in 1Pet 1:1
The chief town of Bithynia was Nicaea, celebrated for the general Council of the Church held there in A.D. 325 against the Arian heresy.
Bibliography Information Smith, William, Dr "Definition for 'Bithyn-ia' Smiths Bible Dictionary". bible-history.com - Smiths; 1901.