Fluent

"Fluent" describes the ability to speak, write, or understand a language smoothly and accurately, with ease similar to a native speaker. It involves not just knowing vocabulary and grammar, but also being comfortable using the language in conversation, understanding nuances, and reacting naturally. Fluency suggests a high level of proficiency that allows effective communication without frequent pauses or searching for words. It's often achieved through extensive practice and immersion, enabling a person to express ideas clearly and respond quickly in various contexts.