Fussy

The most appropriate antonym of the word fussy is patient.

• Fussy means "complaining or difficult to please."
• Patient means "able to bear pain or annoyance without complaining."

The other words do not have the same meaning as fussy and are therefore not antonyms.

• Irritable means "easily annoyed or made angry."
• Nervous means "feeling or showing anxiety or nervousness."
• Restless means "unable to stay still or quiet."