VH

VH is an acronym that can refer to several distinct concepts across different fields. Its meaning depends on the context, ranging from biology to aviation, computing, and popular culture.

In immunology, VH denotes the variable region of the heavy chain of an antibody. Immunoglobulins are composed of heavy and light chains; the VH domain is encoded by multiple VH gene segments in the immunoglobulin heavy chain locus and recombines with DH and JH segments to form the antigen-binding site. The VH region, together with a light-chain variable region (VL), contributes to the diversity and specificity of antibodies.

In aviation, VH is the aircraft registration prefix for Australian civilian airplanes. The prefix is followed by up to four alphanumeric characters and is administered by the Australian Civil Aviation Safety Authority. The VH prefix designates registration within Australia's civil registry and appears on aircraft markings for international operations.

In computing and networking, VH can stand for virtual host, a configuration concept that allows a single server to host multiple websites or domains. Web servers use the Host header to route requests to the correct site, enabling multiple virtual hosts on one physical machine or IP address.

In popular culture, VH is commonly used as an abbreviation for the rock band Van Halen, particularly in fan communities and media references. The shorthand appears in discussions of albums, songs, and imagery associated with the band.

Because VH has multiple established meanings, the intended interpretation is determined by the surrounding topic and field of use.