Spanish indefinite words, or indefinidos, are a key part of Spanish grammar and essential for speaking naturally in everyday conversations. These words help learners talk about people, objects, and quantities in a non-specific way using expressions like someone, something, any, or none. Common Spanish indefinidos such as algún, alguna, ningún, ninguna, nadie, and nada are frequently used affirmative and negative sentences. In this post, you’ll find information about how Spanish indefinite words work, how they agree in gender and number, and how to use them correctly with double negation in Spanish grammar. Perfect for A1–A2 Spanish learners who want to improve their fluency and communication skills naturally.