|1.||a number of things growing, fastened, or occurring close together|
|2.||a number of persons or things grouped together|
|3.||(US) 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|
|9.||to gather or be gathered in clusters|
|[Old English clyster; related to Low German Kluster; see |
Atoms and molecules are the smallest forms of matter typically encountered under normal conditions and are in that sense the basic building blocks of the material world. There are phenomena, such as lightning and electric discharges of other kinds, that allow free electrons to be observed, but these are exceptional occurrences. It is of course in its gaseous state that matter is encountered at its atomic or molecular level; in gases each molecule is an independent entity, only occasionally and briefly colliding with another molecule or with a confining wall.
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