The International Standard Bible Encyclopedia, Revised
Expound [Gk. ektíthēmi] (Acts 18:26; 28:23); NEB also “dealt at length”; cf. Acts 11:4, RSV “explain.” The sense of ektîthēmi is accurately conveyed by the English verb “expound”—to set forth vigorously a case in some detail. Thus the RSV is inconsistent in rendering Acts 11:4 with the weaker “explain.”
Compton’s Encyclopedia
fair and exposition
fair and expositionAlthough the terms are now used almost interchangeably, fairs and expositions, or exhibitions, have traditionally not been the same. A fair is a temporary market where buyers and sellers gather to transact business. An exposition is a display of works of art, science, or industry