decimal

Etymology

It is borrowed from Medieval Latin decimālis (“of tithes or tenths”),^[2][3][4][5] from Latin decima (“a tenth part, tithe”), the feminine of decimus (“tenth”), from decem (“ten”),^[3][2][6] from Proto-Indo-European *dekm- (“ten”).^[4] The OED explains it partly as a new formation from decimus with -al, and partly as the Medieval Latin word, which meant having the right to collect tithes or paid as a tithe;^[7] the Shorter Oxford and Oxford's dictionary of current English give it as modern Latin.^[8][9] decimal is recorded from 1520, and the Latin phrase decimalis arithmetica (1617) refers to Stevin's work of 1608, after English.^[7] The Latin ordinal was earlier decumus;^[7][10] its relatives in English include ten, dime, decimate and December.^[6]

Earliest recorded meaning

Relating to tenth parts or to the number ten, reckoning by powers of ten: 1608, in the title of R. Norton's translation of S. Stevin.^[7][3] The OED notes that this first use translates the Middle French disme (“tenth, tithe”).^[7] Etymonline dates the adjective to about 1600.^[4]

Semantic evolution

Weekley notes that the word was first applied to Arabic numerals and only later to decimal fractions, an extension of the same idea;^[11][4] the notation in which places after a point stand for tenths, hundredths and so on is recorded from 1616, in E. Wright's translation of Napier.^[7] Etymonline links the use of the point to Napier, about 1619;^[4] decimal point itself is recorded by 1704 or 1711,^[3][4] and decimal system from 1842.^[3] The noun, a number in decimal notation, dates from 1623 in the OED,^[7] 1641 in Barnhart and 1651 in Merriam-Webster.^[3][12] From 1794 the adjective was used of coinage and weights and measures based on powers of ten.^[7][8] The old sense "of tithes", from the Latin, appeared in English in 1641 and is now historical.^[7][12] Johnson (1755) defined it as "numbered by ten; multiplied by ten".^[13]

Timeline

• 1608 – relating to tenths or to the number ten.^[7][3]
• 1616 – of decimal notation, with places for tenths, hundredths and so on.^[7]
• 1623 – noun, a number written in decimal notation.^[7]
• 1641 – of or relating to tithes.^[7]
• 1704 – decimal point.^[3] Etymonline dates it by 1711.^[4]
• 1794 – of a currency or system of measures based on powers of ten.^[7]
• 1842 – decimal system.^[3]
• 1967 – noun, a decimal currency.^[7]

Meanings

Adjective

1. Based on the number ten; counting or proceeding by tens.^[12][14][7]
2. Expressed as a decimal fraction: the decimal equivalent of three eighths.^[12][14]
3. Using a system of currency or measures in which units are related by powers of ten: decimal coinage.^[7][14]
4. (historical) Relating to tithes.^[7][12]

Noun

1. A fraction whose denominator is a power of ten, written with a decimal point.^[14][12]
2. Any number written in the decimal system.^[14][12][7]

Word family

• decimally
• decimalization
• decimalize
• decimal fraction
• repeating decimal

Related words

• decimate
• dime
• December
• ten
• decade
• deci-

References

1. ^ a b Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
3. ^ a b c d e f g h i Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
4. ^ a b c d e f g Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
5. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
6. ^ a b Ayto, John (2005), Word Origins: The Secret Histories of English Words from A to Z, 2nd ed., London: A & C Black
7. ^ a b c d e f g h i j k l m n o p q r s Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
8. ^ a b Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
9. ^ Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
10. ^ Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
11. ^ Weekley, Ernest (1921), An Etymological Dictionary of Modern English, London: John Murray
12. ^ a b c d e f g Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
13. ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
14. ^ a b c d e Collins English Dictionary (2023), Glasgow: HarperCollins