any collection or assemblage of persons or things; cluster; aggregation:
a group of protesters; a remarkable group of paintings.
a number of persons or things ranged or considered together as being related in some way.
Also called radical. Chemistry. two or more atoms specifically arranged, as the hydroxyl group, –OH.
Geology. a division of stratified rocks comprising two or more formations.
Music. a section of an orchestra comprising the instruments of the same class.
Art. a number of figures or objects shown in an arrangement together.
Mathematics. an algebraic system that is closed under an associative operation, as multiplication or addition, and in which there is an identity element that, on operating on another element, leaves the second element unchanged, and in which each element has corresponding to it a unique element that, on operating on the first, results in the identity element.
Grammar (chiefly British) . a phrase:
nominal group; verbal group.
verb (used with object)
to place or associate together in a group, as with others.
to arrange in or form into a group or groups.
verb (used without object)
to form a group.
to be part of a group.
a number of persons or things considered as a collective unit
a small band of players or singers, esp of pop music
a number of animals or plants considered as a unit because of common characteristics, habits, etc
(grammar) another word, esp in systemic grammar, for phrase (sense 1)
an association of companies under a single ownership and control, consisting of a holding company, subsidiary companies, and sometimes associated companies
two or more figures or objects forming a design or unit in a design, in a painting or sculpture
a military formation comprising complementary arms and services, usually for a purpose: a brigade group
an air force organization of higher level than a squadron
(chem) Also called radical. two or more atoms that are bound together in a molecule and behave as a single unit: a methyl group -CH3 Compare free radical
a vertical column of elements in the periodic table that all have similar electronic structures, properties, and valencies Compare period (sense 8)
(geology) any stratigraphical unit, esp the unit for two or more formations
(maths) a set that has an associated operation that combines any two members of the set to give another member and that also contains an identity element and an inverse for each element
See blood group
to arrange or place (things, people, etc) in or into a group or (of things, etc) to form into a group
1690s, originally an art criticism term, “assemblage of figures or objects in a painting or design,” from French groupe “cluster, group” (17c.), from Italian gruppo “group, knot,” perhaps ultimately from Proto-Germanic *kruppaz “round mass, lump,” and related to crop. Extended to “any assemblage” by 1736. Meaning “pop music combo” is from 1958.
1718 (transitive), 1801 (intransitive), from group (n.). Related: Grouped; grouping.
v. grouped, group·ing, groups
A group G is a non-empty set upon which a binary operator * is defined with the following properties for all a,b,c in G:
Closure: G is closed under *, a*b in G Associative: * is associative on G, (a*b)*c = a*(b*c) Identity: There is an identity element e such that a*e = e*a = a. Inverse: Every element has a unique inverse a’ such that a * a’ = a’ * a = e. The inverse is usually written with a superscript -1.
- Group 3
protocol, compression (G3) The CCITT fax protocol which uses data compression and allows a variety of file types (e.g. electronic mail, pictures, PostScript) to be transmitted over analogue telephone lines. The Group 3 protocol was published by CCITT in 1993. Full details of the protocol are available from ITU-T. See also Group 4. (1998-10-03)
- Group 4
protocol, compression (G4) The CCITT fax protocol which uses data compression and allows a variety of file types (e-mail, pictures, PostScript, etc.) to be transmitted over digital (ISDN) telephone lines. The Group 4 protocol was published by CCITT in 1993. Full details of the protocol are available from ITU-T. See also Group 3. (1998-09-10)
- Group agglutination
group agglutination n. The clumping of antibodies specific for a group of antigens common to several bacteria, each of which possesses its own specific antigen.
- Group agglutinin
group agglutinin n. An agglutinin specific for a group antigen. Also called cross-reacting agglutinin, minor agglutinin, partial agglutinin.