Meanings
official; ministerial (of or by a state or regional authority)
colloquialofficial, confirmed (by any kind of source considered authoritative)
colloquialsignificant, impressive, a lot (especially of values)
1000 Euro für das Gerät? Das ist schon ein amtlicher Preis.1000 euros for that device? That's a pretty significant price./That's quite a lot.
Examples
GermanEnglish
Es gibt keine amtlichen Dokumente.There are no official documents.
Das ist amtlich.It's official.