1: στράτευμα
(Strong's #4753 — Noun Neuter — strateuma — strat'-yoo-mah )

denotes (a) "an army" of any size, large or small, Matthew 22:7; Revelation 9:16; 19:14,19 (twice); (b) "a company of soldiers," such as Herod's bodyguard, Luke 23:11 (RV, "soldiers") or the soldiers of a garrison, Acts 23:10,27 (RV, "the soldiers," for AV, "an army"). See SOLDIER , WAR.

2: στρατόπεδον
(Strong's #4760 — Noun Neuter — stratopedon — strat-op'-ed-on )

from stratos, "a military host," pedon, "a plain," strictly denotes "an army encamped, a camp;" in Luke 21:20 , of the soldiers which were to be encamped about Jerusalem in fulfillment of the Lord's prophecy concerning the destruction of the city; the phrase might be translated "by camps" (or encampments).

3: παρεμβολή
(Strong's #3925 — Noun Feminine — parembole — par-em-bol-ay' )

lit., "a casting in among, an insertion" (para, "among," ballo, "to throw"), in the Macedonian dialect, was a military term. In the NT it denotes the distribution of troops in army formation, "armies," Hebrews 11:34; a camp, as of the Israelites, Exodus 19:17; 29:14; 32:17; hence, in Hebrews 13:11,13 , of Jerusalem, since the city was to the Jews what the camp in the wilderness had been to the Israelites; in Revelation 20:9 , the "armies" or camp of the saints, at the close of the Millennium. It also denoted a castle or barracks, Acts 21:34,37; 22:24; 23:10,16,32 .