Dehkhoda Dictionary

The Dehkhoda Dictionary (Persian: لغت‌نامهٔ دهخدا‎‎) is the largest comprehensive Persian dictionary ever published, comprising 16 volumes (more than 27000 pages). The complete work is an ongoing effort that entails over forty-five years of efforts by Ali-Akbar Dehkhoda and a cadre of other experts. Although Dehkhoda covers a big part of literary terms and words in Persian language, it also lacks most of scientific and technology terms coined and loaned during the past decades. Dehkhoda states in the preface of the dictionary that "Not only this book misses 2/3 of today’s entire Persian vocabulary, at least half of the words I knew were forgotten and not recorded in this book." Many of those words were added after his death.

The series initially consisted of 3 million records (فیش fish or برگه bargeh in Persian) (up to 100 records for each word or proper noun) until Dehkhoda's demise in November 1955, and currently contains 343,466 entries that according to the latest digital release of the dictionary by Tehran University Press (version 3.0) are based on an ever-growing library of over 2300 volumes in lexicology and various other scientific fields.

It was first printed in 1931. Dehkhoda also was helped by prominent linguists Mohammad Moin, Jafar Shahidi, and Dabirsiyaghi.

The work became so significant that in 1945, a bill was proposed in the Majles, signed by numerous Members of Parliament, including Mohammed Mossadegh, to allocate a special budget and staff to completing the project. Offices were provided for the task inside the compounds of the Majles itself, and later on, the entire project was moved to University of Tehran College of Humanities, with additional staffing, where the Dehkhoda Institute was founded, and where it remains until this day.

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