Why is it das Department?

Department ends in -ment, and nouns ending in -ment are neuter: in a German dictionary, 97% of them take das.

All nouns ending in -ment
Sense 1
das

Meaning

[1] Official name of the highest administrative authorities in the United States of America

[1] offizielle Bezeichnung der höchsten Verwaltungsbehörden in den Vereinigten Staaten von Amerika

[2] Department at American and British universities

[2] Fachbereich an amerikanischen und britischen Universitäten

Examples

[1]

[1]

Declension

1 Singular Plural
Nominativ das Department die Departments
Genitiv des Departments der Departments
Dativ dem Department den Departments
Akkusativ das Department die Departments

Pronunciation

Dictionary entries include material from Wiktionary. Wiktionary