1: χίλιοι
(Strong's #5507 — Adjective — chilioi — khil'-ee-oy )

"a thousand," occurs in 2—Peter 3:8; Revelation 11:3; 12:6; 14:20; 20:2-7 .

2: χιλιάς
(Strong's #5505 — Noun Feminine — chilias — khil-ee-as' )

"one thousand," is always used in the plural, chiliades, but translated in the sing. everywhere, except in the phrase "thousands of thousands," Revelation 5:11 .

Mark 5:13Acts 2:41Matthew 15:3816:10Mark 8:9,20Acts 21:38Matthew 14:2116:9Mark 6:4418:19Luke 9:14John 6:10Romans 11:4Luke 12:1Acts 21:20Acts 19:19Jude 1:14Revelation 5:11 Revelation 9:16 INNUMERABLE. 1—Corinthians 4:1514:19Matthew 18:24