EASTON’S BIBLE DICTIONARY (1897 EDITION)
Achaichus – (1 Cor. 16:17), one of the members of the church of Corinth who, with Fortunatus and Stephanas, visited Paul while he was at Ephesus, for the purpose of consulting him on the affairs of the church.
These three probably were the bearers of the letter from Corinth to the apostle to which he alludes in 1 Cor. 7:1.