General terms:
* Speech - This is the most common and straightforward term.
* Oral communication - This emphasizes the spoken aspect of communication.
* Verbal communication - This is broader and includes written communication as well, but often used specifically for spoken language.
More specific terms:
* Phonetics - Focuses on the physical production and perception of speech sounds.
* Phonology - Studies how sounds are organized and used in a language.
* Articulatory phonetics - Studies the movements of the vocal tract in speech production.
* Acoustic phonetics - Studies the physical properties of speech sounds.
* Speech science - Combines phonetics, acoustics, and physiology to understand speech production and perception.
* Speech pathology - Focuses on the diagnosis and treatment of speech disorders.
* Voice science - Specifically studies the voice production system.
* Rhetoric - Focuses on the art of effective speaking, including argumentation, persuasion, and delivery.
* Elocution - Focuses on the clear and expressive delivery of speech.
The most appropriate term depends on the specific context and the focus of the study.