Fluent (adjective)

1. Able to speak or write a particular language easily and well.
2. Able to express oneself easily and articulately.
3. Able to move or flow smoothly and easily.

Origin:

Late 16th century: from latin fluent- "flowing", from the verb fluere.

Examples:

1. She is fluent in French and Spanish.
2. He gave a fluent speech without notes.
3. She had a fluent style of writing.
4. The water in the stream was fluent.
5. The dancer's movements were fluent.