「Vehicles on all sides」as with an army on the move, refers to the MILITARY, ARMY: vehicles are vital for moving war materiel. Recall that there were no high-speed roadway systems full of semi-tractor trailer 18-wheeler big rigs initially, and the only time most anyone would see「vehicles on all sides」would be when an army was passing by. Mnemonic: perhaps a「vehicle bound on all sides」today might represent a tank, armored personnel carrier, battleship, stealth bomber, etc. Or, vehicles drawn into a circle, as in 'circle the wagons' for defense by placing them on all sides.
　「Surrounded by rotation of plugging orifice」may refer to spearing enemy bodies, and/or to the involuntary terms of conscription into the military required by liege lords.「Surrounded rotation with filled orifices」could very well be the sages' description of the MILITARY practice of using captured females/ males/ ewes as sex slaves that in more contemporary times are referred to as spearing, plugging, penetration of so-called 'comfort women' travelling with the troops—only gangs of thugs or the military have the might to bring along a gaggle of sex slaves for use during the journey.「Vehicle surrounded on all sides」by the waiting lines of soldiers.「Covered vehicles」were the MEATWAGONS, used by the soldiers with women prostitutes, as the ambulances, hearses, and portable kitchens. Note that the sages often were disparaging of war, armies, soldiering, and such: not when used for defense of course, but when used as a means of killing time and otherwise filling long afternoons of boredom, or war for the sake of war itself, or for the redistribution of wealth from one unfair condition to simply a different unfair condition. Then there is God Almighty's take on this matter, found in Deuteronomy 21:10 When you go to war…and you take captives, 11 if you notice among the captives a beautiful woman and are attracted to her, you may take her as your wife. 12 Bring her into your home…then you may go to her and be her husband and she shall be your wife. 14 If you are not pleased with her, let her go wherever she wishes. You must not sell her or treat her as a slave, since you have dishonored her.

Modern definitions (that generally disregard history) …excluding politically incorrect concepts and other meanings deemed offensive today; may list only pigeonholed definitions, euphemisms, or meaningless mnemonics)
Chinese: army; military; arms
Japanese: war, battle, campaign, fight, troops, forces, army
Unihan extended: army, military; soldiers, troops
EDRDG: army; force; troops; war; battle