It is heir.
Adoption was a way of making family alliances. Heirless emperors also adopted someone to designate him as his heir.
Masculine
It is masculine.
The word "jardin" is masculine in French.
masculine
Masculine. Normally, nouns that end in O in Spanish are masculine.
Feminine
Masculine
In French, "apricot" (abricot) is a masculine noun.
Masculine
"Bolígrafo" is masculine in Spanish.
Masculine