HBO (Home Box Office) is is an American premium cable and satellite television network. “B.O.” is old 1930s slang for “body odor.”

“Horrible Body Odor” (or “Horrible Body Odour,” using a British spelling) is an HBO nickname that has been cited in print since at least 2003 (for “Horrible Body Odor") and 2004 (for “Horrible Body Odour").


Wikipedia: HBO
HBO (Home Box Office) is an American premium cable and satellite television network owned by Home Box Office, Inc., a subsidiary of WarnerMedia Entertainment. The programming featured on the network consists primarily of theatrically released motion pictures and original television shows, along with made-for-cable movies, documentaries and occasional comedy and concert specials.

(Oxford English Dictionary)
B.O. n. body odour.
1933 Sat. Evening Post 14 Jan. 91/3 Those ‘B.O.’ ads. I laughed at—is the joke on me?
1936 W. H. Auden & C. Isherwood Ascent of F6 ii. iii. 96 And some I know have got B.O.: But these are not for me.

Google Groups: rec.sport.pro-wrestling
Hey Test, HBO = Home Box Office
CptainDan
4/7/03
Horrible Body Odor.

Urban Dictionary
HBO
Horrible body odor.
Dude 1: Man that dude has HBO!
Dude 2: Horrible body odor!
by qwerewq March 10, 2004

Google Groups: rec.humor
Re: geroge bush is an ass
Pollywolly
10/27/04
(...)
>> *You* watch HBO?
>
> What is HBO?

Horrible Body Odour.  Other than that it’s a television network in the States - watching it has the same effect as in encountering horrible body odour.

Twitter
Pat Lewis
@patlewis
When I was a kid we used to ask people if they had HBO and if they said yes we told them it stood for “Horrible Body Odor.”
1:16 PM · Feb 21, 2008·Twitter Web Client

Twitter
jeffrey_abbott
@jeffrey_abbott
My wife told a joke last night “Do you have HBO?” “Um no”, “So you don’t have horrible body odor”. D’oh!
8:29 AM · Dec 3, 2009·Twitter Web Client

Twitter
UnkDaBoss PayDayEnt
@UnkAlmighty
If U Don’t Have HBO (Horrible Body Odor) You’ll Be at K-LOUNGE 2Night!
12:42 PM · Apr 16, 2010·Twitter Web Client

Twitter
Thomas Pluck🦊
@thomaspluck
I remember when I was 8, we used to ask other kids “Do you have HBO?” and then say “you have Horrible Body Odor?!” and laugh.
4:32 PM · Nov 18, 2010·TweetDeck

Twitter
Martin Dimech
@martin_dimech
HBO - Horrible Body Odour #BadChannels
6:00 PM · Nov 15, 2013·Twitter for Android

Urban Dictionary
H.b.o.
Slang. Horrible body odor.
Bro! That guy has H.b.o.! Wtf is that?! It’s horrible body odor!
by B-rizzle February 14, 2019

Twitter
mᎥᏦᎬ ᏞᎥᏆᎬᏒᎪᏞᏞᎽ✪
@SkippyMcGizzard
The H in HBO stands for horrible.
The BO stands for B.O.
2:05 AM · Aug 6, 2019·Twitter for Android