A body containing two or more divisions of a large army, organized as a complete army in itself.(noun)
Gnu Collaboartive International Dictionary of English: licensed under The Code Project Open License (CPOL)
Use "army corps" in a sentence
"Your first task should be to aid the French in transportation of their African army corps by covering and if possible bringing to action individual fast German ships, particularly Goeben, which may interfere with that transportation …."
"The German army corps deployed in its sector of the front was conducting a fighting withdrawal toward Oskol."
"The objective of the attack was to free the three German army corps surrounded in the Cherkassy (Korsun) Pocket."