Why is it der Initiator?

Initiator ends in -or, and almost all nouns ending in -or are masculine: in a German dictionary, 93% of them take der.

All nouns ending in -or
Sense 1
der

Meaning

[1] Initiator of an event, even in the broader sense the one who carries out/accompanies it

[1] Veranlasser eines Ereignisses, auch im weiteren Sinne derjenige, der es durchführt/begleitet

Examples

[1] Who was the initiator of this development

[1] Wer war denn der Initiator dieser Entwicklung?

[1] Bob Geldof was the initiator of Live Aide

[1] Bob Geldof war der Initiator von Live Aid.

Declension

1 Singular Plural
Nominativ der Initiator die Initiatoren
Genitiv des Initiators der Initiatoren
Dativ dem Initiator den Initiatoren
Akkusativ den Initiator die Initiatoren

Pronunciation

Dictionary entries include material from Wiktionary. Wiktionary