First Declension Singular, Gen or Dat?

The predominant letter in the ending forms of this declension is a. The nominative singular form consists of the stem and the ending -a, and the genitive singular form is the stem plus -ae.
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First declension (a stems)

1. What gender is 1st declension?
2. What is the genitive singular of 1st declension?
3. Are all 1st declension nouns feminine?

What gender is 1st declension?

Nouns are divided into groups called declensions. Nouns that end in '-a' belong to the first declension. They are mostly feminine.

What is the genitive singular of 1st declension?

Latin words of the first declension have an invariable stem and are generally of feminine gender. The predominant letter in the ending forms of this declension is a. The nominative singular form consists of the stem and the suffix -a, and the genitive singular form is the stem plus -ae.

Are all 1st declension nouns feminine?

Nouns of the 1st declension are feminine, with the exception of nouns which are masculine from their signification (nauta, sailor).