The Detroit nod is often seen in "the trenches" and more violent streets of Detroit. With Detroit being one of the murder capitals of America, any social interaction must be handled carefully. The "Detroit Nod" is a social gurantee that there are no problems and no worries. Essientially; I won't hurt you, you won't hurt me.
In Detroit: "Cuz gave me the nod so I knew he was straight"
"Why that dude nod at people like that?"
"That's the Detroit nod bro!"
"Why that dude nod at people like that?"
"That's the Detroit nod bro!"
by Big Dog Barretta November 24, 2019