A half bar is half of a 9 bar
(yes we are talking about drugs here)

a 9 bar is 9oz of either weed or solid, so a half bar is 4.5oz
How much for a half bar mate?
The person is looking for 4 and a half oz of gear
by TFnk June 14, 2007
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When your penis is at half length and is an inconveience.
Boy 1: Man wtf is in ur pants?

boy 2: dude i got a half bar shutup
by echo_33 January 10, 2007
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To have half an erection.
*looking at cleavage*: "I've got half a bar right now"
by TurboPhoenix October 21, 2011
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50 pence. Or one half of one Great British Pound. A pound coin is gold in colour, hence the reference to a gold bar.
Blokeinnapub 1 "Oy! 'Ow much firra game o' pool iniss shittol 'en?"
Blokkeinnapub 2 "Arf a bar mate anna taker to er fuckincleaners annaw"
by flatley June 6, 2005
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