Abbreviation of Alberta: a province of Canada.
What is AB?
• Initialism of Artium baccalaureus.
• Initialism of Aryan Brotherhood, a US white supremacist, neo-Nazi prison gang and crime syndicate.
• Initialism of Anheuser-Busch.
(Noun) Initialism of able seaman or able-bodied seaman.
• Initialism of afterburner.
• Initialism of aid to the blind.
• Initialism of airbase.
• Abbreviation of alkylbenzene.
• Initialism of antibody.
• Initialism of artificial breeding.
• Initialism of assembly bill.
• A blood type of the ABO system that has both blood antigens and may receive all blood types, and donate to AB.
• A person with this blood type.
• Initialism of adult baby.
• Initialism of asymmetric bars.
• A halal snack pack consisting of doner meat topped with chips, tomato sauce, chilli sauce, barbecue sauce, and garlic sauce.
(Adjective) Initialism of airborne.
• Initialism of antiballistic.
• Initialism of at bat.
Why AB matters
AB appears in U.S. legal practice across multiple practice areas. Knowing what it means — and when it applies — can determine the outcome of motions, filings, and negotiations. For non-lawyers, the value of looking up a precise definition is that legal terms often carry meanings that differ from everyday usage; relying on the common meaning can lead to costly missteps.
How AB works in practice
In practice, AB is invoked when parties, judges, or attorneys need to identify the legal status of an issue, the rights of those involved, or the procedural step required next. The definition shown above is sourced from Wiktionary , which is widely cited in U.S. legal practice. Because U.S. law is jurisdictionally layered — federal, state, and sometimes local — the precise application of the term can vary by court, so check the controlling authority for your specific case.