Top definition
One and-a-half times as much as something.
"Indeed, the first year of the office's ad campaign, ABC grabbed nearly $30 million worth, half again as much as Fox, its nearest rival at $20 million."

Source: Article on US Gov't Pot Propaganda
by Adam Laughlin September 04, 2005
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2
Those 'rare' birthdays where the number for the age, when read from left to right, the second number is half of the first. For example 21, 42, 63 and 84 are Halfagain birthdays. This applies only to two digit birthdays, if you're 105 that's special enough in itself chumley.
My dad decided to help me celebrate my first halfagain birthday by giving me my first beer!

Jeanne is celebrating her next to last halfagain birthdays at burning man this year.
by Doc Primo Herb November 25, 2018
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