1. a person who adjusts musical instruments to the correct pitch
2. an electronic device that receives radio or television signals
3. a device used to adjust the pitch of musical instruments

Examples

• The piano tuner comes to our house twice a year.
• She used an electronic tuner to tune her guitar.
• The radio tuner wasn’t picking up any clear stations.
• He works as a professional piano tuner.
• The guitar tuner showed that the E string was flat.
• We need to replace the tuner in our old stereo system.
• The violin tuner carefully adjusted each string.