Meaning of controlled vocabulary in English:
controlled vocabulary
noun
1A limited range of words used in teaching a person (now especially a child) to read at a particular level, with new items gradually being introduced as reading skills advance.
2(In information science) a prescribed set of terms which may be used in abstracting, indexing, etc., and which is recognized within that system as having a predetermined set of meanings.
Origin
1920s; earliest use found in Classical Weekly.
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