noun (1)
\ ˈhōst How to pronounce host (audio) \

Definition of host

 (Entry 1 of 5)

1 : army the destruction of Pharaoh's host in that sea— W. L. Sperry
2 : a great number : multitude a whole host of options


verb (1)
hosted; hosting; hosts

Definition of host (Entry 2 of 5)

intransitive verb

: to assemble in an army usually for a hostile purpose


noun (2)
plural hosts

Definition of host (Entry 3 of 5)

1a : a person who receives or entertains guests socially, commercially, or officially Ourself will mingle with society / And play the humble host.— William Shakespeare … another blog disclosed that he [John Edwards] had been the host of an off-the-record dinner with several bloggers at his house in Washington.Time On Thursday night, [Dawn] Staley will be the host at a black tie fundraising dinner for her foundation in suburban Philadelphia.The New York Times … the Inn at Little Washington has become one of America's premier dining destinations, a cozy world of casual luxury and terrific American food created by chef Patrick O'Connell and host Reinhardt Lynch.— Thomas Matthews
b : a place or organization that provides facilities and services for an event or function The night before he scored 18 points and got 18 rebounds to help Winthrop beat host UNC-Asheville 75-62.— Seth Davis For the pleasure of visitors who like to combine running and jumping with more intellectual pursuits, Olympic hosts have traditionally set forth a generous display of cultural events. Seoul came up to snuff.— E. J. Kahn, Jr.
c : a country, government, etc. that agrees to allow an outside business, organization, group of people, etc. to operate, function, or live within in its boundaries, jurisdiction, or population often used before another noun In short, the problem is that the interests of a large multinational company may not be coincident with the development interests of the host countries.— E. S. Simpson… when a United States service member commits an offense within a foreign country, should the accused be tried in a court-martial or in a court of the host country?— Charles A. Shanor and Timothy P. TerrellAlthough the guest workers were distinct—in the sense that they were initially expected to go home and not be absorbed into the host society—in practice, many have stayed and thereby contributed to the ethnic diversity of Europe.— Michael Chisholm
2a biology : a living organism on or in which a parasite lives … a single-celled protozoan parasite that is able to sexually reproduce in only one host—cats.— Erin Tomb … the parasite larvae develop inside each bee, rapidly consuming their host from the inside out.— Paul Schmid-Hempel Cryptosporidium is an enteric parasite of emerging importance in normal and immunocompromised hosts.— Peter S. Millard et al. … there is a wide array of mechanisms by which the parasite evades or modulates host immunological attack.— Rick M. Maizel et al. — see also definitive host, host cell, intermediate host
b biology : the larger, stronger, or dominant member of a commensal or symbiotic pair When one species, known as the symbiont, lives within the body of the other, known as the host, the relation is called endosymbiotic.— James. J. Childress et al. In a number of natural associations, such as nitrogen-fixing bacteria in legumes, the host organism receives a significant benefit, but the symbiont partner gets little in return.Physics Today
c biology : an individual into which a tissue, part, or embryo is transplanted from another Allogeneic transplantation is more complicated than syngeneic or autologous transplantation because of immunologic differences between donor and host.— Frederick R. Appelbaum This suggests that functional connections develop between the transplanted neural tissue and the host brain.— Gary W. Arendash et al. — see also graft-versus-host disease
3 : a person who talks to guests on a program (such as a radio or television show or a podcast) As chairman of Harpo Entertainment Group, as well as host, star, and supervising producer of The Oprah Winfrey Show, Winfrey is the most successful woman ever to enter the field of television.— Harry Allen Not only was he confident, with a malleable voice that was equal parts game show host and morning-radio DJ, but his jokes were seemingly fully formed.— Peter Rubin As [Randi] Rhodes demonstrates every afternoon drive, a liberal talk radio host can be just as bombastic, hyperbolic, and plain old nasty as a conservative one.— Jason Zengerle The YouTuber and podcast host has gained millions of subscribers with her opinionated brand of energy and excitement.— Vanessa Jackson Even though some YouTube hosts are iconic for rarely showing their faces …, it's typically a good idea to know some basics about hosting a video and honing your online personality.— Shelby Brown — see also cohost
4 : a mineral or rock that is older than the minerals or rocks in it also : a substance that contains a usually small amount of another substance incorporated in its structure Concretions … are discrete bodies—often spheroidal, ellipsoidal, or disk-shaped—with a composition similar to that of the host rock except for the mineral cement, which is frequently calcite, silica, or iron oxide. — Alan M. Cvancara
5 : a computer that controls communications in a network or that administers a database But the malware attached to the fake Air Force e-mail has a more devious—and worrisome—capability … it gives the attacker control over the "host" PC, capturing screen shots and perusing files.— Brian Grow et al. also : server sense 6

— see also play host to


verb (2)
hosted; hosting; hosts

Definition of host (Entry 4 of 5)

transitive verb

1 : to receive or entertain guests at or for host a dinner : to serve as host (see host entry 3 sense 1a) to host friends
2 : emcee hosted a series of TV programs


noun (3), often capitalized

Definition of host (Entry 5 of 5)

religion : the eucharistic bread

Synonyms for host

Synonyms: Noun (1)

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First Known Use of host

Noun (1)

13th century, in the meaning defined at sense 1

Verb (1)

15th century, in the meaning defined above

Noun (2)

14th century, in the meaning defined at sense 1a

Verb (2)

15th century, in the meaning defined at sense 1

Noun (3)

14th century, in the meaning defined above

History and Etymology for host

Noun (1)

Middle English ost, host "army, detachment, body of attendants, multitude, throng," borrowed from Anglo-French, going back to Late Latin hostis "archenemy, the Devil, army," going back to Latin, "foreigner, stranger" (in early use), "enemy," going back to dialectal Indo-European *ghost-i- "outsider, guest" — more at guest entry 1

Note: The use of hostis to mean "army," evident in 6th-century Latin (Gregory the Great, Gregory of Tours), is apparently via the sense shift "enemy" > "enemy army" > "any armed force." For details on the earlier semantic history of Latin hostis see note at guest entry 1.

Verb (1)

derivative of host entry 1

Noun (2)

Middle English ost, host "person who receives guests, guest," borrowed from Anglo-French oste, hoste, going back to Latin hospit-, hospes "guest, visitor, person receiving guests," going back to dialectal Indo-European *ghosti-pot- (whence probably also Old Church Slavic gospodĭ "lord, master"), from *ghost-i- "outsider, guest" + *pot- "one in control, master" — more at guest entry 1, potent entry 1

Note: The dual meanings "host"/"guest" of Latin hospes and its progeny are due to customs of reciprocity: a person serving as guest on one occasion would act—and be expected to act—as host on another occasion to a visiting former host. Both Latin hospes and Slavic gospodĭ have undergone a considerable degree of phonetic reduction from their putative etymons—in particular in the Slavic case, where Latin unstressed syllable reduction and syncope were not at play—leading some to question the correctness of the etymologies. Parallel compounds with the same second element are Greek despótēs "master, lord" (going back to *dems-pot- "master of the house"; see despot), Sanskrit dámpatiḥ "householder, lord of the house," Avestan də̄ṇg paitiš; Sanskrit viśpátiḥ "chief of a settlement/tribe," Avestan vīspaitiš, Lithuanian viẽšpats "lord" (with outcomes of Indo-European *u̯iḱ-, *u̯oiḱ- "house, community"; see vicinity).

Verb (2)

Middle English hosten, osten, derivative of ost, host host entry 3

Noun (3)

Middle English hoste, oste "sacrificial offering, bread consecrated in the Eucharist," borrowed from Anglo-French hoste, hoiste, going back to Late Latin hostia "Eucharist," going back to Latin, "sacrificial animal," derivative from the base of hostīre "to recompense, requite," hostis "foreigner, stranger, enemy" — more at guest entry 1

Learn More About host

Time Traveler for host

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The first known use of host was in the 13th century

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Cite this Entry

“Host.” Dictionary, Merriam-Webster, Accessed 16 Aug. 2022.

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More Definitions for host


\ ˈhōst How to pronounce host (audio) \

Kids Definition of host

 (Entry 1 of 4)

1 : a person who receives or entertains guests
2 : a living animal or plant on or in which a parasite lives


hosted; hosting

Kids Definition of host (Entry 2 of 4)

: to serve as host to or at host friends hosting a party



Kids Definition of host (Entry 3 of 4)

: multitude We faced a host of problems.


noun, often capitalized

Kids Definition of host (Entry 4 of 4)

: the bread used in Christian Communion


\ ˈhōst How to pronounce host (audio) \

Medical Definition of host

1 : a living organism on or in which a parasite lives — see definitive host, host cell, intermediate host
2 : the larger, stronger, or dominant one of a commensal or symbiotic pair
3a : an individual into which a tissue or part is transplanted from another
b : an individual in whom an abnormal growth (as a cancer) is proliferating

More from Merriam-Webster on host

Nglish: Translation of host for Spanish Speakers

Britannica English: Translation of host for Arabic Speakers


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