For "eonian" Webster's dictionary says:
" lasting for an immeasurably or indefinitely long period of time"
The other two translations referred to an "age":
From the beginning of the link i gave you:
Jonah was in the fish forever [olam]. But only until he left three days later (Jon. 1:17; 2:6).
¨ Sodom’s fiery judgment is eternal [olam]. But only until God returns them to their former state (Ez. 16:53-55; Ju. 7).
¨ A Moabite is forbidden to enter the Lord’s congregation forever [olam]. But only until the 10th generation. (De. 23:3).
¨ Hills are everlasting [olam]. But only until made low and the earth is burned up (Ge. 49:26; De. 33:15; Is. 40:4; 2Pe. 3:10).
¨ Mountains are everlasting [olam]. But only until they are scattered (Hab. 3:6).
¨ A slave serves his master forever [olam]. But only until death ends his servitude (Ex. 21:6).
¨ The Mosaic covenant is everlasting [olam]. But only until it vanishes away (Le. 24:8; He. 8:7-13).
¨ The Aaronic priesthood is everlasting [olam]. But only until the likeness of Melchizedek arises (Ex. 40:15; Nu. 25:13; He. 7:14-22).
¨ These “stones” are to be a memorial forever [olam]. Where are they now (Jos. 4:7)?
¨ The leprosy of Naaman shall cling forever [olam]. But only until his death, of course (2K. 5:27).
¨ God dwells in Solomon’s temple forever [olam]. But only until it is destroyed (2Ch. 7:16; 1K 8:13; 9:3).
¨ Animal sacrifices were to be offered forever [olam]. But only until ended by the work of Christ (2Ch. 2:4; He. 7:11-10:18).
¨ Circumcision was an everlasting [olam] covenant. But only until the new covenant (Ge. 17:9-13; 1Co. 7:19; Ga. 5:6).
¨ Israel’s judgment lasts forever [olam]. But only until the Spirit is poured out and God restores it (Is. 32:13-15).
¨ I will make you an eternal [olam] excellence. But only until many generations (Is. 60:15).
As we can see, olam does not mean “eternal” though it can last a very long time.
Thirty five [35] OT verses which define the word “olam.”
Exodus 3:15
(15) And God said moreover unto Moses, Thus shalt thou say unto the children of Israel, The LORD God of your fathers, the God of Abraham, the God of Isaac, and the God of Jacob, hath sent me unto you: this is my name for ever,[עולם/olam] and this is my memorial unto all generations.
In this vs. “name olam” is paired with “unto all generations.” “Age(s),”a finite period, does not equate to “unto all generations,”“for ever” does.
Psalms 21:4
(4) He asked life of thee, and thou gavest it him, even length of days for ever [עולם/olam] and ever.[עד/ad]
In this vs. “olam” is paired with “length of days”. “Age(s),” a finite period, does not equate to length of days, “for ever and ever” does.
Psalms 45:17
(17) I will make thy name to be remembered in all generations: therefore shall the people praise thee for ever [עולם/olam] and ever:[עד/ad]
In this vs. “olam” is paired with “in all generations,” “Age(s),” a finite period, does not equate to “in all generations”, “for ever and ever” does.
Psa 33:11
(11) The counsel of the LORD standeth for ever, [ עולם] the thoughts of his heart to all generations.
In this vs. “standeth olam” is paired with “to all generations,”“age(s),” a finite period, does not equate to “to all generations,” “for ever” does.
Psa 146:10 The LORD will reign for ever, [עולם/olam] Thy God, O Zion,
unto all generations. Hallelujah.[“ all generations” also Ps 100:5, 106:31]
In this vs. “reign olam” is paired with “unto all generations,”“age(s),” a finite period, does not equate to “to all generations,” “for ever” does.
Psa 37:28
(28) For the LORD loveth judgment, and forsaketh not his saints; they are preserved for ever: [ עולם/olam] but the seed of the wicked shall be cut off.
In this vs. “preserved olam” is contrasted with “the wicked shall be cut off,””age(s),”a finite period, is not opposite of “the wicked shall be cut off,” “for ever” is.
Ecc 3:14
(14) I know that, whatsoever God doeth, it shall be for ever:[ עולם] nothing can be put to it, nor any thing taken from it: and God doeth it, that men should fear before him.
In this vs. עולם/olam is equated with. “nothing can be added or taken away” from God's acts. “Age(s),“a finite period, does not equate with “nothing can be added or taken away” from God's acts, “for ever” does.
Isa 51:6
(6) Lift up your eyes to the heavens, and look upon the earth beneath: for the heavens shall vanish away like smoke, and the earth shall wax old like a garment, and they that dwell therein shall die in like manner: but my salvation shall be for ever, [ עולם] and my righteousness shall not be abolished.
In this vs. “salvation olam” is equated with “shall not be abolished”, “age(s),” a finite period, is not opposite of “shall not be abolished,” “forever” is.
Isa 51:8
(8) For the moth shall eat them up like a garment, and the worm shall eat them like wool: but my righteousness shall be for ever, [ עולם] and my salvation from generation to generation.
In this vs. “righteousness olam” is paired with “from generation to generation” “age(s),”a finite period, does not equate to “from generation to generation.” “for ever” does.
Dan 7:14
(14) He was given authority, glory and sovereign power; all nations and peoples of every language worshiped him. His dominion is an everlasting [ עולם] dominion that will not pass away, and his kingdom is one that will never be destroyed.
In this vs. “olam dominion” is equated with “will not pass away” and “never be destroyed.” “Age(s),” a finite period, does not equate to “will not pass away,””never be destroyed”, “everlasting dominion” does.
Jer 23:40
(40) I will bring on you everlasting disgrace [ עולם]—everlasting shame [ עולם] that will not be forgotten."
In this vs. “olam disgrace and shame” is paired with “will not be forgotten.” “age(s) a finite period, does not equate to “will not be forgotten,””everlasting” does.
Jer 50:5
(5) They will ask the way to Zion and turn their faces toward it. They will come and bind themselves to the LORD in an everlasting [ עולם] covenant that will not be forgotten.
In this vs. “olam covenant” is paired with “will not be forgotten,””age(s),” a finite period, does not equate to “will not be forgotten,” ”everlasting” does.
Exo 27:21
(21) In the tabernacle of the congregation without the vail, which is before the testimony, Aaron and his sons shall order it from evening to morning before the LORD: it shall be a statute for ever [עולם/olam] unto their generations on the behalf of the children of Israel.
In this verse עולם/olam is paired with “unto their generations.” “Age(s)” does not equate to “unto their generations,” “for ever” does.
Exo 30:21
(21) So they shall wash their hands and their feet, that they die not: and it shall be a statute for ever [עולם/olam] to them, even to him and to his seed throughout their generations.
[“throughout their generations “ also Lev 10:9, 17:7, 23:14, 23:21, 23:41, Num 10:8, 15:15, 18:23, Psa 145;13, Ex 40:15, Lev 7:36][/indent]
In this verse “statute עולם/olam” is paired with “die not” and “throughout their generations.” “Ages” does not equate to “die not” and “throughout their. Generations,” “forever” does.
Psa 45:17
(17) I will make thy name to be remembered in all generations: therefore shall the people praise thee for ever [עולם/olam] and ever.[ עד/ad][“in all generations” also Ps 100:5, 106:31].
In this verse עולם/olam and . עד/ad are paired with “in all generations.” “Age(s)” does not equate to “in all generations,” “for ever and ever” does.
Psa 148:6
(6) He hath also stablished them for ever [עולם/olam] and ever:[ עד/ad] he hath made a decree which shall not pass.
In this verse עולם/olam and עד/ad are paired with “shall not pass.” “Age(s)” does not equate to “shall not pass.” “forever and ever” does.
Isa 55:13
(13) Instead of the thorn shall come up the fir tree, and instead of the brier shall come up the myrtle tree: and it shall be to the LORD for a name, for an everlasting [ עולם/olam] sign that shall not be cut off.”
In this verse “ עולם/olam sign” is paired with ”shall not be cut off.” “Age(s)” does not equate to “shall not be cut off.” “everlasting does.
[26]Isa 56:5
(5) Even unto them will I give in mine house and within my walls a place and a name better than of sons and of daughters: I will give them an everlasting [ עולם/olam] name, that shall not be cut off.
In this verse “ עולם/olam name” is paired with ”shall not be cut off.” “Age(s)” does not equate to “shall not be cut off.” “everlasting” does.
Jer 32:40
(40) And I will make an everlasting “[עולם/olam] covenant with them, that I will not turn away from them, to do them good; but I will put my fear in their hearts, that they shall not depart from me.
In this verse “עולם/olam covenant” is paired with “I will not turn away” and ”they shall not depart from me.” “Age(s)” does not equate to “I will not turn away” and “they shall not depart from me.” “everlasting” does.
Jer 50:5
(5) They shall ask the way to Zion with their faces thitherward, saying, Come, and let us join ourselves to the LORD in a perpetual [עולם/olam] covenant that shall not be forgotten.
In this verse “עולם/olam covenant” is paired with ”shall not be forgotten” “Age(s)” does not equate to “shall not be forgotten.” “perpetual covenant” does.
Lam 5:19
(19) Thou, O LORD, remainest for ever; “[עולם/olam] thy throne from generation to generation.
In this verse “עולם/olam” is paired with “from generation to generation.” “Age(s) does not equate to “from generation to generation”, “for ever” does.
Dan 4:3
(3)(3:33) How great are His signs! and how mighty are His wonders! His kingdom is an everlasting [עלם/alam] kingdom, and His dominion is from generation to generation.[עם־דר ודר/am-dor w’dor]
In this verse [עלם/alam] is paired with “from generation to generation.”
“Age(s) does not equate to “from generation to generation”, “for ever” does.
