The first such dictionary to use a defining vocabulary was the New Method English Dictionary by Michael West and James Endicott (published in 1935), a small dictionary written using a defining vocabulary of just 1490 words.
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When the Longman Dictionary of Contemporary English was first published in 1978, its most striking feature was its use of a 2000-word defining vocabulary based on Michael West's General Service List, and since then defining vocabularies have become a standard component of monolingual learner's dictionaries for English and for other languages.
Vocabulary OneSource | Short Trips: Defining Patterns | National Vocabulary Championship | Australian English vocabulary |