History

In antiquity, Philo of Byblos authored the first text that could now be called a thesaurus. In Sanskrit, the Amarakosha is a thesaurus in verse form, written in the 4th century.
The first modern thesaurus was Roget's Thesaurus, first compiled in 1805 by Peter Mark Roget, and published in 1852. Since its publication it has never been out of print and is still a widely used work across the English-speaking world.[2] Entries in Roget's Thesaurus are listed conceptually rather than alphabetically. Roget described his thesaurus in the foreword to the first edition:
It is now nearly fifty years since I first projected a system of verbal classification similar to that on which the present work is founded. Conceiving that such a compilation might help to supply my own deficiencies, I had, in the year 1805, completed a classed catalogue of words on a small scale, but on the same principle, and nearly in the same form, as the Thesaurus now published.[3]