naturaleza
/natuɾaˈleθa/ · A2 · noun · f
nature
🌳 natural + -eza (the -ness ending) = natural-ness, i.e. nature
Spanish builds abstract nouns from adjectives with -eza: bello → belleza, triste → tristeza. So natural → naturaleza. All -eza nouns are feminine, which gives you the gender for free: la naturaleza.