Maybe it helps if I also explain why these nouns are neutral in German and Dutch despite describing a feminine object. It is because of the diminutive, which is a marker to make it smaller. In Dutch there is also a form without this marker "de meid" which gets the feminine article. The more common form, however, is "het meisje" which has the neutral form because of describing a "small" girl. Leaving out the diminutive, practically, only happens in expressions like "grote meid" (big girl). In German it would be even rarer to say Mädchen without the diminutive -chen.
This is comparable with the Spanish -ito
I am still new to Greek, but I guess the same applies here.
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