Art. 4 No. 14 GDPR:

"Biometric data" means

"personal data resulting from specific technical processing relating to the physical, physiological or behavioural characteristics of a natural person, which allow or confirm the unique identification of that natural person, such as facial images or dactyloscopic data"

Identical definition in Art. 3 (33) COM Proposal 2021/206 (Artificial Intelligence Act) [Kachel D.94].