apology: [16] The original meaning of apology was ‘formal self-justification’, often used as the title of a piece of writing rebutting criticism (as in the Apology of Sir Thomas More, knight 1533). This is indicative of the word’s origins in Greek apologíā, a derivative of the verb apologeisthai ‘speak in one’s defence’, formed from the prefix apo- ‘away, off’ and logos ‘speech’ (source of English logic).
It entered English through either French apologie or Latin apologia (which was separately borrowed into English as a Latinism in the late 18th century). The meaning ‘expression of regret for offence given’ developed in the late 16th century. => logic[apology etymology, apology origin, 英语词源]