“A source of confusion is that ‘citron’ in French and English are false friends, as the French word ‘citron’ refers to what in English is a lemon; whereas the French word for the citron is ‘cédrat’.
…
Other languages that use variants of citron to refer to the lemon include Armenian, Czech, Dutch, Finnish, German, Estonian, Latvian, Lithuanian, Hungarian, Esperanto, Polish and the Scandinavian languages.[citation needed]”
What do you mean by “Citrons” that just means lemon in French and I’ve never heard it used in English.
https://en.wikipedia.org/wiki/Citron
For the lazy:
“A source of confusion is that ‘citron’ in French and English are false friends, as the French word ‘citron’ refers to what in English is a lemon; whereas the French word for the citron is ‘cédrat’.
…
Other languages that use variants of citron to refer to the lemon include Armenian, Czech, Dutch, Finnish, German, Estonian, Latvian, Lithuanian, Hungarian, Esperanto, Polish and the Scandinavian languages.[citation needed]”
Same reaction here, Zitrone in German is lemon.
But it seems this is an issue for many language pairs, they have a section on it on Wikipedia: https://en.wikipedia.org/wiki/Citron#Other_languages