short for "roger that" or "roger."
Radio code used to notify to the other party that you understand or received and acknowledge the transmission.
Can also be used in person between two or more people, but if used over texted messaging, most people won't understand because they are stupid.
Harry#1 "Harry, there is a Delia at your 6 O'clock, does she have a Fox Brav?"
Harry#2 "Negative Harry, thats not a Fox Brav, its just a nasty outbreak of scabies"
Harry#1 "Rog, thats gross"
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