@Cerberus The word certainly has changed in meaning, but it came from Greek
apologia (ἀπολογία), that the apostles used in the New Testament as a "defense" in a trial (Acts 26:2) or in "giving an answer" to an inquiry for why Christians have hope in the midst of suffering/persecution (1 Peter 3:15) (see
Etymology). Only later it seems to be associated with giving answers to difficulties regarding a religion.