The English word apologetics sounds an awful lot like the word apology (from apologize, as in saying you are sorry for something you did). These words are, however, not so closely related. The English word apologetics comes from the Greek word avpologi,a (apologian) which is used in the following verses (quoted from the English Standard Version):
1 Peter 3: 15
but in your hearts regard Christ the Lord as holy, always being prepared to make a defense to anyone who asks you for a reason for the hope that is in you;ku,rion de. to.n Cristo.n a`gia,sate evn tai/j kardi,aij u`mw/n( e[toimoi avei. pro.j avpologi,an panti. tw/| aivtou/nti u`ma/j lo,gon peri. th/j evn u`mi/n evlpi,doj(
Philippians 1:7
It is right for me to feel this way about you all, because I hold you in my heart, for you are all partakers with me of grace, both in my imprisonment and in the defense and confirmation of the gospel.Kaqw,j evstin di,kaion evmoi. tou/to fronei/n u`pe.r pa,ntwn u`mw/n dia. to. e;cein me evn th/| kardi,a| u`ma/j( e;n te toi/j desmoi/j mou kai. evn th/| avpologi,a| kai. bebaiw,sei tou/ euvaggeli,ou sugkoinwnou,j mou th/j ca,ritoj pa,ntaj u`ma/j o;ntajÅ
Philippians 1:16
The latter do it out of love, knowing that I am put here for the defense of the gospel.oi` me.n evx avga,phj( eivdo,tej o[ti eivj avpologi,an tou/ euvaggeli,ou kei/mai(
2 Corinthians 7:11
For see what earnestness this godly grief has produced in you, but also what eagerness to clear yourselves (NASB: “what vindication of yourselves”), what indignation, what fear, what longing, what zeal, what punishment! At every point you have proved yourselves innocent in the matter.ivdou. ga.r auvto. tou/to to. kata. qeo.n luphqh/nai po,shn kateirga,sato u`mi/n spoudh,n( avlla. avpologi,an( avlla. avgana,kthsin( avlla. fo,bon( avlla. evpipo,qhsin( avlla. zh/lon( avlla. evkdi,khsinÅ evn panti. sunesth,sate e`autou.j a`gnou.j ei=nai tw/| pra,gmatiÅ
2 Corinthians 12:19
Have you been thinking all along that we have been defending ourselves to you? It is in the sight of God that we have been speaking in Christ, and all for your upbuilding, beloved.Pa,lai dokei/te o[ti u`mi/n avpologou,meqaÅ kate,nanti qeou/ evn Cristw/| lalou/men\ ta. de. pa,nta( avgaphtoi,( u`pe.r th/j u`mw/n oivkodomh/jÅ
Acts 24:10
And when the governor had nodded to him to speak, Paul replied: "Knowing that for many years you have been a judge over this nation, I cheerfully make my defense.VApekri,qh te o` Pau/loj neu,santoj auvtw/| tou/ h`gemo,noj le,gein\ evk pollw/n evtw/n o;nta se krith.n tw/| e;qnei tou,tw| evpista,menoj euvqu,mwj ta. peri. evmautou/ avpologou/mai(
Acts 25:8
Paul argued in his defense, "Neither against the law of the Jews, nor against the temple, nor against Caesar have I committed any offense."tou/ Pau,lou avpologoume,nou o[ti ou;te eivj to.n no,mon tw/n VIoudai,wn ou;te eivj to. i`ero.n ou;te eivj Kai,sara, ti h[martonÅ
Acts 25:16
I answered them that it was not the custom of the Romans to give up anyone before the accused met the accusers face to face and had opportunity to make his defense concerning the charge laid against him.pro.j ou]j avpekri,qhn o[ti ouvk e;stin e;qoj ~Rwmai,oij cari,zesqai, tina a;nqrwpon pri.n h’ o` kathgorou,menoj kata. pro,swpon e;coi tou.j kathgo,rouj to,pon te avpologi,aj la,boi peri. tou/ evgklh,matojÅ
Acts 26:24
And as he was saying these things in his defense, Festus said with a loud voice, “Paul, you are out of your mind; your great learning is driving you out of your mind.”Tau/ta de. auvtou/ avpologoume,nou o` Fh/stoj mega,lh| th/| fwnh/| fhsin\ mai,nh|( Pau/le\ ta. polla, se gra,mmata eivj mani,an peritre,peiÅ
Acts 22:1
“Brothers and fathers, hear the defense that I now make before you.”
:Andrej avdelfoi. kai. pate,rej( avkou,sate, mou th/j pro.j u`ma/j nuni. avpologi,ajÅ
2 Timothy 4:16
At my first defense no one came to stand by me, but all deserted me. May it not be charged against them!
VEn th/| prw,th| mou avpologi,a| ouvdei,j moi parege,neto( avlla. pa,ntej me evgkate,lipon\ mh. auvtoi/j logisqei,h\
Romans 2:15
They show that the work of the law is written on their hearts, while their conscience also bears witness, and their conflicting thoughts accuse or even excuse them (NASB: “their thoughts alternately accusing or else defending them”)
oi[tinej evndei,knuntai to. e;rgon tou/ no,mou grapto.n evn tai/j kardi,aij auvtw/n( summarturou,shj auvtw/n th/j suneidh,sewj kai. metaxu. avllh,lwn tw/n logismw/n kathgorou,ntwn h’ kai. avpologoume,nwn(
1 Corinthians 9:3
This is my defense to those who would examine me.
~H evmh. avpologi,a toi/j evme. avnakri,nousi,n evstin au[thÅ
Jeremiah 38:6 (31:6 in English)
The Greek translation of the Old Testament (called the LXX, or the Septuagint) uses the word:For there shall be a day when watchmen will call in the hill country of Ephraim: ‘Arise, and let us go up to Zion, to the LORD our God.’”
[ti e;stin h`me,ra klh,sewj avpologoume,nwn evn o;resin Efraim avna,sthte kai. avna,bhte eivj Siwn pro.j ku,rion to.n qeo.n h`mw/n
Conclusion
Based on these references it is clear that the word avpologi,a (and its cognates) refers to defending, making a defense, giving reasons or excuses (without the modern connotation of giving bad excuses), and so on. The thing being defended could range anywhere from the Gospel, to a person (such as Paul’s defense of himself before Felix).-------
http://eyeonapologetics.com/blog/2010/08/04/where-does-the-word-%E2%80%9Capologetics%E2%80%9D-come-from/