Decimal

How to spell decimal

7 letters · 3 syllables

How to pronounce decimal

Say the part in capitals loudest.

What does decimal mean?

1. adjectiveRelating to or based on a system of counting in tens.
2. nounA fraction expressed in figures after a point, in the base-ten system.

Decimal in a sentence

• adjective

  The spreadsheet rounds every figure to two decimal places.

• noun

  She converted the fraction into a decimal before adding the values.

• adjective

  The country switched to a decimal currency in 1971.

• noun

  The calculator displayed the result as a long decimal.

Where does decimal come from?

Language of origin: Latin

The word comes from the Latin decimalis, meaning 'relating to a tenth', which was built on decimus, the ordinal word for 'tenth', from decem, meaning 'ten'. English picked it up in the early 1600s, originally as a mathematical adjective for systems and fractions based on grouping things in tens. The same decem root sits inside a surprising family of English words: December (once the tenth month of the old Roman calendar), 'dime' (a tenth of a dollar), and even 'decimate', which literally meant to punish a mutinous Roman legion by killing every tenth man. Because the whole idea is built on tens, the spelling keeps a single c and a single m, with the tricky middle vowel being an unstressed schwa that sounds like nothing in particular. Remembering the link to decem and the ordinal decimus helps fix that quiet 'i' in deci-mal.

How the word is built

• decim- (from Latin decimus: tenth, itself from decem: ten)
• -al (adjective/noun suffix)