- a combining form meaning “tenth,” used in words denoting units of the metric system (deciliter); on this model, extended to other systems (decibel).
- denoting one tenth; 10 –1decimetre Symbol: d
in the metric system, word-forming element denoting weights of one-tenth of the standard unit of measure, 1801, from French deci-, taken arbitrarily from Latin decimus “tenth,” from decem “ten” (see ten).
- One tenth (10-1):decibel.
- A prefix that means one tenth, as in deciliter, one tenth of a liter.