numeral
twelve
A1
Twelve; the cardinal numeral for 12. 'Zwölf' is used for counting, telling time (zwölf Uhr) or quantities. It’s invariable as a numeral (ordinal form is 'zwölfte'). No specific preposition or auxiliary. Spelled regularly and not declined when used as a number, but declines appear when used adjectivally.
Examples
Das Treffen sollte um zwölf beginnen, doch viele Teilnehmer kamen zu spät, sodass die Veranstaltung später startete.
The meeting was supposed to start at twelve, but many participants arrived late, so the event started later.
Es ist zwölf Uhr.
It's twelve o'clock.
Details
Mnemonics
Picture a dozen eggs — twelve items: 'zwölf'.
Notes
Commonly used for hours (zwölf Uhr) and counting to twelve.