faculties
n. C / Un. the natural abilities of your mind or body, such as the ability to think, see, or hear. People often use this word when talking about staying sharp as they get older.
n. the inherent mental or physical powers of an individual, such as reason, memory, or sight. Usually used in the plural to refer to the collective state of a person's cognitive or sensory abilities.
He is ninety years old but still has all his faculties.
The witness was asked if she was in full possession of her faculties when she signed the legal document.
Medical ethics require that a patient be in full possession of their mental faculties before they can provide informed consent for a major surgical procedure.
Almost always used in the plural ('faculties') when referring to mental or physical powers; the singular 'faculty' often refers to a department in a university.