This is a translation of the 2nd edition of the Dictionnaire de Science du sol, which was published in France in 1990. The 1st edition of the dictionary was published in 1986 in the French language. This dictionary contains the definitions of nearly 2800 words relating to general soil science, mineralogy, petrology, micromorphology, geomorphology, and also the major systems of classification. The changes which have taken place in soil science in the last few years have been incorporated. To cite only the most important, there have been the work of the Subcommission on Soil Micromorphology of the International Society of Soil Science, the amendments to Soil Taxonomy, and the Revised Legend for the FAO-UNESCO Soil Map of the World, in which the definition of the diagnostic horizons and properties have been specially reviewed. The authors also introduced or brought up-to-date: many other terms, particularly those in the areas of mineralogy, agricultural hydrology, and surface hydrology. The present edition also includes the official translation of the soil classification of the Federal Republic of Germany, which is particularly interesting for semiterrestrial and subaquatic soils.