mode

of vibration
synonyms: vibration, vibration mode
https://doi.org/10.1351/goldbook.08637
Independent vibrational motion of a molecule.
Note:
In vibrational spectroscopy 'mode' or 'vibration' is used for normal mode of vibration.
Source:
PAC, 2021, 93, 647. 'Glossary of methods and terms used in analytical spectroscopy (IUPAC Recommendations 2019)' on page 754 (https://doi.org/10.1515/pac-2019-0203)