Latin numerals: Numbers with English Equivalents

(Latin-Roman Numerals that are used in English and other modern languages)

Numbers are the common denominator of everyday life, as essential to modern society as language.

—Andrea Sutcliffe

Cardinals followed by ordinals

1, I
unus (unus [masculine], una [feminine], unum [neuter]): one; primus (prima, primum), first.
diurnal: Happening once a day.
annual: Happening once a year.
2, II
duo (duae, duo): two; secundus (secunda, secundum), second. There are no gender distinctions after II (two), except when such are indicated as with 200 through 900 and some of the ordinals.
semidiurnal: Happening twice a day.
biannual: Happening twice a year.
biennial: Happening every second year.
biweekly: Happening twice a week or every two weeks.
semiweekly: Happening twice a week.
semimonthly: Happening twice a month.
bimonthly: Happening twice a month or once every two months.
biyearly: Happening twice a year or every two years.
semiannual: Happening twice a year.
3, III
tres (tria): three; tertius (tertia, tertium), third.
triweekly: Happening three times a week or every three weeks.
quattuor: four; quartus (quarta, quartum), fourth.
quadrennial: Happening once in four years.
5, V
quinque: five; quintus (quinta, quintum), fifth.
quinquennial: The fifth anniversary.
6, VI
sex: six; sextus (sexta, sextum), sixth.
sexennial: The sixth anniversary.
7, VII
septem: seven; septimus (septima, septimum), seventh.
septennial: The seventh anniversary.
octo: eight; octavus (octava, octavum), eighth.
octennial: The eighth anniversary.
novem: nine; nonus (nona, nonum), ninth.
novennial: The ninth anniversary.
10, X
decem: ten; decimus/decumus (decima, decimum), tenth.
decennial: The tenth anniversary.
11, XI
undecim: eleven; undecimus, eleventh.
12, XII
duodecim: twelve; duodecimus, twelfth.
13, XIII
tredecim: thirteen; tertius decimus, thirteenth.
quattourdecim: fourteen; quartus decimus, fourteenth.
15, XV
quindecim: fifteen; quintus decimus, fifteenth.
16, XVI
sedecim: sixteen; sextus decimus, sixteenth.
17, XVII
septemdecim: seventeen; septimus decimus, seventeenth.
duodeviginti, octodecim: eighteen; duodevicesimus,
, eighteenth.
undeviginti, novemdecim: nineteen; undevicesimus,
, nineteenth.
20, XX
viginti: twenty; vicesimus, twentieth.
vicennial: The twentieth anniversary.
21, XXI
viginti unus, unus et viginti: twenty-one; unetvicesimus,
vicesimus primus
, twenty-first.
22, XXII
duoetviginti: twenty-two; duoetvicesimus, twenty-second.
duodetriginta: twenty-eight; duodetricesimus, twenty-eighth.
undetriginta: twenty-nine; undetricesimus, twenty-nineth.
30, XXX
triginta: thirty; tricesimus, thirtieth.
duodequadraginta: thirty-eight;
duodequadragesimus, thirty-eighth.
undequadraginta: thirty-nine; undequadragesimus, thirty-ninth.
40, XL, XXXX
quadraginta: forty; quadragesimus, fortieth.
duodequinquaginta: forty-eight;
duodequinquagesimus, forty-eighth.
undequinquaginta: forty-nine; undequinquagesimus, forty-ninth.
50, L
quinquaginta: fifty; quinquagesimus, fiftieth.
semicentennial: The fiftieth anniversary.
60, LX
sexaginta: sixty; sexagesimus, sixtieth.
70, LXX
septuaginta: seventy; septuagesimus, seventieth.
80, LXXX
octoginta: eighty; octogesimus, eightieth.
nonaginta: ninety; nonagesimus, ninetieth.
100, C
centum: one hundred; centesimus, hundredth.
centennial: The hundredth anniversary.
101, CI
centum (et) unus: one hundred one; centesimus (et) primus, hundred first.
sesquicentennial: The one-hundred fiftieth anniversary.
200, CC
ducenti (ducentae, ducenta): two hundred; ducentesimus, two hundredth.
bicentennial: The two-hundredth anniversary.
bisemicentennial: The two-hundred fiftieth anniversary.
300, CCC
trecenti (trecentae, trecenta): three hundred; trecentesimus, three hundredth.
tricentennial, tercentenary: The three-hundredth anniversary.
trisemicentennial, tersemicentennial: The three-hundred fiftieth anniversary.
400, CD, CCCC
quadringenti (quadringentae, quadringenta): four hundred; quadringentesimus, four hundredth.
quadricentennial: The four-hundredth anniversary.
quadrisemicentennial: The four-hundred fiftieth anniversary.
500, D
quingenti (quingentae, quingenta): five hundred; quingentesimus, five hundredth.
quincentennial: The five-hundredth anniversary.
quinsemicentennial: The five-hundred fiftieth anniversary.
600, DC
sescenti (sescentae, sescenta): six hundred; sescentesimus, six hundredth.
700, DCC
septingenti (septingentae, septingenta): seven hundred;
septingentesimus, seven hundredth.
800, DCCC
octingenti (octingentae, octingenta): eight hundred;
octingentesimus, eight hundredth.
900, CM, DCCCC
nongenti (nongentae, nongenta): nine hundred;
nongentesimus, nine hundredth.
1 000, M
mille: one thousand; millesimus, one thousandth.
2 000, MM
duo milia: two thousand; bis millesimus, two thousandth.

X (10) is formed by joining an inverted V to the bottom of the usual symbol V for five.
L (50) represents the lower part of C (100) without the curve of the C.
C (100) stands for the initial letter of centum.
D (500) is a combination of L and a reversed C [the symbol meaning “times ten” or 50 times 10 = 500].
M (1 000) stands for the initial letter of mille.
Source: Living Latin, A contemporary Approach, Book Two
—Clara Ashley, Ruth Fiesel, and Austin Lashbrook
(Skokie, Illinois: National Textbook Co., 1981), p. 340.

Additional Latin years for anniversaries compiled from several sources

  • Biennial - 2 years
  • Triennial - 3 years
  • Quadrennial - 4 years
  • Quinquennial - 5 years
  • Sexennial or Hexennial - 6 years
  • Septennial - 7 years
  • Octennial - 8 years
  • Novennial - 9 years
  • Decennial - 10 years
  • Hendecennial - 11 years
  • Duodecennial - 12 years
  • Tredecennial - 13 years
  • Quindecennial - 15 years
  • Sextodecennial - 16 years
  • Septendecennial - 17 years
  • Vigintennial - 20 years
  • Trigentennial - 30 years
  • Quadragennial - 40 years
  • Semicentennial or Quinquagenary - 50 years
  • Sexagennial - 60 years
  • Septuagennial - 70 years
  • Demisesquicentennial or Septuagesiquintennial - 75 years
  • Octogintennial - 80 years
  • Nonagintennial - 90 years
  • Centennial - 100 years
  • Quasquicentennial - 125 years
  • Sesquicentennial - 150 years
  • Septaquintaquinquecentennial or Terquasquicentennial - 175 years
  • Bicentennial - 200 years
  • Quasquibicentennial - 225 years
  • Semiquincentennial - 250 years
  • Tercentennial or Tricentennial - 300 years
  • Quadricentennial or Quatercentenary - 400 years
  • Quincentennial - 500 years
  • Sexacentennial - 600 years
  • Septuacentennial or Septcentennial - 700 years
  • Octocentennial - 800 years
  • Nonacentennial - 900 years
  • Millennial - 1000 years
  • Bimillennial - 2000 years
  • Quindecimillenial - 15 000 years

Pointing to a page about a Greek numbers. Extensive information about Greek numerals.

Pointing to a page about a Greek numbers. Unit of numer- or "number" words.