Why is it der Uruguayer?

Uruguayer ends in -er, and most nouns ending in -er are masculine: in a German dictionary, 86% of them take der.

All nouns ending in -er
Sense 1
der

Meaning

[1] Citizens of Uruguay

[1] Bürger von Uruguay

Examples

[1]

[1]

Declension

1 Singular Plural
Nominativ der Uruguayer die Uruguayer
Genitiv des Uruguayers der Uruguayer
Dativ dem Uruguayer den Uruguayern
Akkusativ den Uruguayer die Uruguayer

Pronunciation

Dictionary entries include material from Wiktionary. Wiktionary