To go out of one's way to help or provide a service to a friend/colleague/acquaintance. Often in exchange for nothing. Another way of describing a favor or act of altruism.
For example:

'I going KFC, what you having for lunch?' 'Got no money, do you want to Hook a brother up?' 'Okay I will HBU and get a bucket.'
by james hooha March 7, 2012
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A request of information/access to something (often illegal) from one homeboy to another.
Homeboy A - "Yo nigga, I got me a fly new hat stand"

Homeboy B - "Yo yo yo my man, Hook a brother up"

by LaShaun Jackson1 January 27, 2009
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not having to wait an hour for a butter chicken in Lazeez
John Smith: "How come Ahmed got his tikka massalla before us?"

Jane Doe: "Beanie man was hooking a brother up"
by Rabaat March 9, 2009
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