The definition of a datum is a fact used to make a conclusion or a point of reference in geography or geology.(noun)
See datum in Webster's New World College Dictionary
Origin: L, what is given, neut. of datus: see date
See datum in American Heritage Dictionary 4
Origin: Latin, something given
Origin: , from
Origin: neuter past participle of dare, to give; see dō- in Indo-European roots.
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