Explanation of the Difference Between Soil & Dirt

Dirt

• The word, according to the Oxford English Dictionary, descends from Middle English, possibly from Old English or Old Icelandic. Its primary meanings include "excrement," "unclean matter" such as soil and mud, or "useless material." Other definitions say that dirt is a substance dug out of the ground. There is even a 16th century verb, as in, "Don't dirt the floor." Dirt, it would appear, is a substance, a material; separate from the earth underneath.

Soil

• Soil descends from Old French. Its oldest meanings refer to a muddy place where wild boars wallow or a pool or place used as refuge by a hunted animal. A soiled place may be fouled by sewage or other filth and the word is still used as a verb -- to soil a towel, for example. Using these primary definitions, soil seems to refer to a place, a location on or in the earth.

Considerations

• Considering that the first definitions of dirt and soil came from different language sources and that the earliest written definitions appeared in the 15th and 16th centuries, these two words have had a long time to adapt to new languages and local usage. There are dirt farmers and soil scientists. Those who till the soil tend to think of it as dirt and those who study it refer to it as soil. Modern farmers, however, till the soil and send soil samples off for testing to determine which fertilizers will work best on their crops. The top- and subsoil of the earth is a living membrane of sand, rock, humus and dying tissue, darkest on the surface and taking its coloring from the minerals that give it substance.

Significance

• Like any language, time and culture adapt and alter the meanings and usage of English words, indigenous as well as borrowed. Among their numerous definitions and usages, many of which, thankfully, have passed out of usage, soil and dirt seem to both refer to the substance in the top few feet of the planet, known as topsoil and subsoil. This layer is called soil and scientists analyze it to understand the history of a specific section of Earth. Dig a bit of it out and you'll just have dirt.