bh

BH is an abbreviation and code that may refer to several distinct concepts depending on context. Common uses include a country designation, a term in physics, and shorthand in health care and linguistics.

In geography and politics, BH is the ISO 3166-1 alpha-2 code for Bahrain, an island nation in the Persian Gulf. Its internet country code top-level domain is .bh. The country is a constitutional monarchy with Manama as its capital.

In astrophysics, BH denotes a black hole, a region of spacetime from which nothing can escape due to extreme gravity. Key features include an event horizon and, depending on mass, stellar-mass or supermassive categories. Black holes are central to studies of gravitation and high-energy phenomena.

In condensed matter physics, BH stands for the Bose-Hubbard model, a theoretical framework describing interacting bosons on a lattice. It explains quantum phase transitions between superfluid and Mott-insulator states and is used in cold-atom experiments.

In health care, BH commonly stands for behavioral health, covering mental health and substance use services and related support systems.

In linguistics, "bh" is a digraph used in transliteration and orthography to represent aspirated sounds in some Indic languages, and is used in Sanskrit transliteration to denote a breathy-voiced consonant.