International Bittering Units. They measure how bitter a brew is, which you shouldn't worry much about since you'll be making mead, not beer.

International Bittering Unit. Accepted standard for measuring the bitterness of a finished beer. 1 IBU= 1 milligram of iso-alpha acid (acid produced by hops) in 1 liter of beer.

International Bitterness units. A system of indicating the hop bitterness in finished beer.

international bittering units. Measured as parts per million of isomerised hop resins.

An IBU is a measurement of the bitterness imparted by the hops to the beer. Budweiser beer has about eight bittering units; many barley wines have 100 or more.

International Business Unit. A strategic business unit of the Postal Service that focuses exclusively on the international market and is responsible for both household and commercial services. The IBU also is responsible for Army Post Office and Fleet Post Office services.

International Bittering Units. A standard measure of the hop content in beer. Hops Infection. The growth of any microorganism in wort or beer, except for the the brewer’s yeast that was deliberately added. Most infections harm the flavor of the finished product.

International Bittering Units. A measure of the actual bitterness level of beer. 1 IBU = 1 part per million of isomerized alpha acid.

International Bitterness Units. An internationally-agreed scale for measuring the bitterness of beer. A "lite" American lager may have around 10 IBU's, an English mild ale around 20 units, an India Pale Ale 40 or higher, an Irish stout 55 to 60 and barley wine 65.

International Bittering Unit. The accepted method of expressing hop bitterness in beer. PPM of dissolved iso-alpha acids present in beer.

International Bittering Units. A more precise unit for measuring hops. Equal to the AAU multiplied by factors for percent utilization, wort volume and wort gravity.