Definitions

1. adjective

having no tone or melody; lacking musical quality

“The singer’s toneless performance disappointed the audience.”

2. adjective

showing no emotional response or interest; apathetic

“She was accused of being toneless when her friend broke the news about their breakup.”

3. noun

a quality of being toneless, especially in music or singing

“The judge criticized the singer’s tonelessness, saying it was unprofessional.”