age (redirected from age groups)

age

1. 

a. a period of history marked by some feature or characteristic; era

b. (capital when part of a name): the Middle Ages; the Space Age

2. Geology palaeontol

a. a period of the earth's history distinguished by special characteristics

b. the period during which a stage of rock strata is formed; a subdivision of an epoch

3. Myth any of the successive periods in the legendary history of man, which were, according to Hesiod, the golden, silver, bronze, heroic, and iron ages

4. Psychol the level in years that a person has reached in any area of development, such as mental or emotional, compared with the normal level for his chronological age

5. of age adult and legally responsible for one's actions (usually at 18 or, formerly, 21 years)

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age [āj]

(biology)

Period of time from origin or birth to a later time designated or understood; length of existence.

(geology)

Any one of the named epochs in the history of the earth marked by specific phases of physical conditions or organic evolution, such as the Age of Mammals.

One of the smaller subdivisions of the epoch as geologic time, corresponding to the stage or the formation, such as the Lockport Age in the Niagara Epoch.

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AGE

(aerospace engineering)

aerospace ground equipment