Host can mean:

• In general English, the term host can refer to a person, organisation, animal, cell, computer or similar that receives guests or intruders
• In television or radio, the host of a show is the person who presents it - for example Jay Leno is the current host of The Tonight Show.
• In biology, a host organism harbors a parasite, mutual partner, or commensal partner, typically providing nourishment and shelter. A host can also refer to a cell infected by a virus See host (biology) for detail and also symbiosis
• In psychology and mental health, a host represents the most important (to therapeutic goals) mental entity in someone who has Dissociative Identity Disorder (DID, formerly known as Multiple Personality Disorder or MPD). See host (psychology)
• In Japan, a host, a male gigolo, provides an entertainment service for females. See host club (Japan)
• In informatics, host serves as a synonym of server
• Host , an album released by the heavy metal/goth metal band Paradise Lost in 1999
• A host may also consist of a large group, such as an army or a large number of people under a single cause or banner. Typical usage in English might generate the clause: "a host of US troops invaded Iraq in 2003". In the Bible, the heavenly host means "chorus or army of angels"
• In Roman Catholicism, the host names the transubstantiated bread in the Eucharist. See also viaticum
• In host-guest chemistry a host molecule, such as a receptor, can receive a guest, such as a ligand
• In computing, a host file, stored on the computer's filesystem, serves to look up the Internet Protocol address of a device connected to a computer network
• Often used as a short term for WebHost (A company or individual who offers webspace and somtimes a domain name in exchange for services or money.)