A day that represents a gang's initials, street, numbers, area code, etc. Typically grounds to hold a party, drink-up, run back on rivals, etc.
Ex. 1

"The Rollin’ 100’s hood day is October 10th. "

Footnote in P. v. Walker, May 5, 2023

Ex. 2

ChiChi: Hey fool! It's July 27! Hood Day for the Gay Boy Gangsters!

Culo: No way holmes! What's up with that?

ChiChi: G = 7 B =2 G =7... GBG = 7/27...Get it? Hood Day!

Culo: So what we gonna do to celebrate Hood Day?

ChiChi: Get the Crisco and man wipes and find out.
by ZXY&ABC May 6, 2023
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A "hood up day" is a phrase used to describe any day for which:

One's physiological state is less than preferable on awakening.

AND the course of action taken to rectify this situation is to conduct the daily routine in a hooded sweatshirt with the hood of the aforementioned sweatshirt up over one's head.

causes for a hood up day may include: flu, swine flu, man flu, female "tummy aches", TVOD, GFDI (girlfriend disengagement illness), BFDI (boyfriend disengagement illness), embarassment, lazyness, depression, cock blocking, WBCFS (work backlog chronic fatigue syndrome), FPS withdrawal syndrome, being mauled by a bear, failing an exam, rape, car sickness, realisation of lack of funds, watching "marley and me", bad night's sleep, no night's sleep, post mid day nap dizziness, dehydration, hunger, bad hair day, failure (all forms) and rejection

However the most common cause of a hood up day is the consumption of copious ammounts of alcohol the previous night, resulting in a catostrophic hangover.
Example 1 (as an exclaimation, and an explaination)
man 1: oh, hi steve i was wonderi...
man 2(interupts): HOOD UP DAY!
man 1: ok maybe later.

Example 2 (used in a phone convesation)
girl 1:hi
girl 2:oh, hiya jen
girl 1:seriously becca, you have to come over and make me feel better i'm having a massive hood up day
girl 2:i'm on it i've got the little mermaid on dvd, but you need to decide, cookie dough or phish food
by pigaloo November 14, 2009
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