What does dementing mean?
"Dementing" is the present participle of the verb "to dement," which means to deprive someone of their mind or drive them mad. In contemporary English it survives chiefly as a clinical adjective describing illnesses or processes that cause dementia — progressive, usually irreversible decline in memory, thinking, and reasoning. Doctors and researchers thus speak of a "dementing illness" or a "dementing process" to identify the underlying condition responsible for cognitive deterioration, most commonly Alzheimer's disease. The word derives from the Latin de- (away from) plus mens, mentis (mind), literally meaning to unseat the mind. Outside medicine, the older sense — something so distressing that it unhinges a person — is now rare and literary. When writing about people affected by such conditions, modern style guides favor person-first phrasing, reserving "dementing" for the pathology rather than the individual.
(Of an illness or pathological process) causing dementia; producing progressive loss of memory, cognition, and reasoning.
"Creutzfeldt–Jakob disease is a rapidly dementing condition."
Almost entirely confined to medical literature and formal clinical discussion.
Present participle of "dement": to drive mad; to deprive of reason or mental balance.
"He wrote that the endless suspicion was dementing the old king."
This sense is now rare, literary, or archaic; it does not appear in ordinary modern usage.
Doctors rarely say a patient 'has become demented' anymore — instead they speak of a 'dementing illness,' shifting the blame from the person to the disease.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of dementing
"Dementing" traces back to the verb "dement," formed in English from Latin de- ("away from") combined with mens, mentis ("mind") — literally, to unman or unsound the mind. The root mens is the same that gives us "mental," "mind" itself via Germanic cognates, and "dementia," coined in Latin as the state of being out of one's mind. The verb entered English in the early modern period, and its participle later took on a specialized clinical role in describing disorders that produce dementia.
Related word forms
How dementing is actually used
In modern usage, "dementing" appears almost exclusively in medical and clinical writing, where it functions adjectivally before nouns like "illness," "disease," or "process" to describe conditions that cause dementia. The older, general sense of driving someone mad is now rare and somewhat literary or archaic. Because "dement" and its forms can sound stigmatizing when applied directly to people, careful writers prefer person-first language such as "a person living with dementia."
Easily confused with dementing
"Demented" describes a person already affected by dementia or madness, while "dementing" describes something that causes that condition.
"Dementia" is the noun for the syndrome of cognitive decline itself; "dementing" is the adjective describing whatever brings it about.