Oxford English Dictionary | Dictionary of National Biography | dictionary | Webster's Dictionary | Dictionary | The New Grove Dictionary of Music and Musicians | Brewer's Dictionary of Phrase and Fable | Macquarie Dictionary | The Oxford Dictionary of Quotations | Dictionary of New Zealand Biography | Dictionary.com | Cyclopaedia, or an Universal Dictionary of Arts and Sciences | ''Classical Dictionary'' | Century Dictionary | Benezit Dictionary of Artists | A Dictionary of the English Language | Webster's Third New International Dictionary | Urban Dictionary | The Devil's Dictionary | The American Heritage Dictionary of the English Language | Indo-European Etymological Dictionary | Historical Dictionary of American Slang | General Biographical Dictionary | Dictionary of Literary Biography | Collins English Dictionary | Brockhaus and Efron Encyclopedic Dictionary | Black's Law Dictionary | Biographical dictionary | Australian National Dictionary Centre | Australian Dictionary of Biography |
Most applicable to teaching, e.g. the Longmans defining dictionary of the simplest meanings of 2,000 English words is used to define the 4,000 most basic English idioms -- this is a core glossary of the English language, which permits access to the core ontology (the idioms).