senilis

Senilis is a Latin adjective meaning “of old age” or “old,” and in English it is closely related to the words senile and senility. The term appears in medical and scientific vocabularies as a qualifier for age-related conditions, rather than as a disease name by itself. Its usage reflects a historical association of certain declines with aging.

In medical contexts, senilis is most often encountered as a descriptor for conditions tied to aging, such as senile dementia, senile cataract, or senile osteoporosis. Historically, the phrase senile dementia referred broadly to memory and cognitive decline in older adults. In modern practice, clinicians increasingly use age-related or late-onset language and specify the underlying causes when possible (for example, Alzheimer’s disease or vascular dementia rather than the blanket term “senile dementia”). Similarly, senile cataract describes cataract formation commonly seen with advancing age.

In biology and taxonomy, senilis can appear as a Latin descriptor in species names or descriptions to denote features associated with older life stages, though it is not a universal or consistently applied taxonomic marker. More often, contemporary biological writing relies on terms such as senescence or age-related changes to describe the broader process of aging at the cellular or organismal level.

See also: senescence; dementia in older adults; age-related diseases; elderly.