cluster
n
1 a number of things growing, fastened, or occurring close together
2 a number of persons or things grouped together
3 (U.S. military) a metal insignia worn on a medal ribbon to indicate a second award or a higher class of a decoration or order
a a group of bombs dropped in one stick, esp. fragmentation and incendiary bombs
b the basic unit of mines used in laying a minefield
5 (Astronomy) an aggregation of stars or galaxies moving together through space
6 a group of two or more consecutive vowels or consonants
7 (Statistics) a naturally occurring subgroup of a population used in stratified sampling
a a chemical compound or molecule containing groups of metal atoms joined by metal-to-metal bonds
b the group of linked metal atoms present
vb
9 to gather or be gathered in clusters (Old English clyster; related to Low German Kluster; see clod, clot) ♦
clustered adj ♦
clusteringly adv ♦
clustery adj
cluster bomb
n a bomb that throws out a number of smaller bombs or antipersonnel projectiles when it explodes
cluster fly
n a dipterous fly, Pollenia rudis, that tends to gather in large numbers in attics in the autumn: family Calliphoridae. The larvae are parasitic in earthworms
gear cluster
n (Engineering) an assembly of gears permanently attached to a shaft
globular cluster
n (Astronomy) a densely populated spheroidal star cluster with the highest concentration of stars near its centre, found in the galactic halo
oak-leaf cluster
n (U.S) an insignia consisting of oak leaves and acorns awarded to holders of certain military decorations to indicate a further award of the same decoration
tone cluster
n (Music) a group of adjacent notes played simultaneously, either in an orchestral score or, on the piano, by depressing a whole set of adjacent keys