Literally, it's a fellow soldier Figuratively, it means someone who has shared a difficult, dangerous or stressful experienceIt can also be two soldiers that protect each other in a war
It usually means that if you give the item to a courier company (usually, before a specified time) they will get it to its destination for the start of business the next day.
The definition of Spatial order is the order of where things are placed. For instance, an example would be: My room is a mess! To the far left of my room is a moldy half-eaten pizza laying up against...