In Italian, ordinal numbers from 11 and beyond are formed by dropping the last vowel and adding “-esimo” at the end. Ordinal numbers between 11 and 19 are as follows:
| undici | 11 | undicesimo/-a/-i/-e | 11.o / 11.a/ 11.i / 11.e |
| dodici | 12 | dodicesimo/-a/-i/-e | 12.o / 12.a/ 12.i / 12.e |
| tredici | 13 | tredicesimo/-a/-i/-e | 13.o / 13.a/ 13.i / 13.e |
| quattordici | 14 | quattordicesimo/-a/-i/-e | 14.o / 14.a/ 14.i / 14.e |
| quindici | 15 | quindicesimo/-a/-i/-e | 15.o / 15.a/ 15.i / 15.e |
| sedici | 16 | sedicesimo/-a/-i/-e | 16.o / 16.a/ 16.i / 16.e |
| diciassette | 17 | diciassettesimo/-a/-i/-e | 17.o / 17.a/ 17.i / 17.e |
| diciotto | 18 | diciottesimo/-a/-i/-e | 18.o / 18.a/ 18.i / 18.e |
| diciannove | 19 | diciannovesimo/-a/-i/-e | 19.o / 19.a/ 19.i / 19.e |
Note that ordinal numbers are adjectives and must agree in gender and number with the noun.
Higher Ordinal Numbers
Here are some higher ordinal numbers:
| venti | 20 | ventesimo/-a/-i/-e | 20.o / 20.a/ 20.i / 20.e |
| trenta | 30 | trentesimo/-a/-i/-e | 30.o / 30.a/ 30.i / 30.e |
| quaranta | 40 | quarantesimo/-a/-i/-e | 40.o / 40.a/ 40.i / 40.e |
| cinquanta | 50 | cinquantesimo/-a/-i/-e | 50.o / 50.a/ 50.i / 50.e |
| sessanta | 60 | sessantesimo/-a/-i/-e | 60.o / 60.a/ 60.i / 60.e |
| settanta | 70 | settantesimo/-a/-i/-e | 70.o / 70.a/ 70.i / 70.e |
| ottanta | 80 | ottantesimo/-a/-i/-e | 80.o / 80.a/ 80.i / 80.e |
| novanta | 90 | novantesimo/-a/-i/-e | 90.o / 90.a/ 90.i / 90.e |
| cento | 100 | centesimo/-a/-i/-e | 100.o / 100.a/ 100.i / 100.e |
| duecento | 200 | duecentesimo/-a/-i/-e | 200.o / 200.a/ 200.i/ 200.e |
| trecento | 300 | trecentesimo/-a/-i/-e | 300.o / 300.a/ 300.i/ 300.e |
| quattrocento | 400 | quattrocentesimo/-a/-i/-e | 400.o / 400.a/ 400.i/ 400.e |
| cinquecento | 500 | cinquecentesimo/-a/-i/-e | 500.o / 500.a/ 500.i/ 500.e |
| seicento | 600 | seicentesimo/-a/-i/-e | 600.o / 600.a/ 600.i/ 600.e |
| settecento | 700 | settecentesimo/-a/-i/-e | 700.o / 700.a/ 700.i/ 700.e |
| ottocento | 800 | ottocentesimo/-a/-i/-e | 800.o / 800.a/ 800.i/ 800.e |
| novecento | 900 | novecentesimo/-a/-i/-e | 900.o / 900.a / 900.i/ 900.e |
| mille | 1.000 | millesimo/-a/-i/-e | 1000.o/1000.a/1000.i/1000.e |
Names of Kings & Queens
Numbers following the names of kings and queens are ordinal and, unlike in English, do not use the definite article before the number.
For example, “Elisabetta Seconda”(Elizabeth the Second), “Edoardo Terzo”(Edward the Third), “Luigi Quattordicesimo”(Louis the Fourteenth), etc.
Fractional Numbers
Fractional numbers in Italian are identical to the ordinal numbers, e.g., “1/16 = un sedicesimo.”
If the numerator is larger than one, the denominator is expressed in plural, e.g., “3/4 = tre quarti.”
Collective Numbers
The collective numbers “un paio” (a pair) and “una dozzina” (a dozen) may also be used to describe quantities.
The adjectives “doppio” and “triplo” are used for “double” and “triple,” respectively.
Other lessons in Level VI:
