| 1. | showing a decline or deterioration of physical strength or mental functioning, esp. short-term memory and alertness, as a result of old age or disease. |
| 2. | of or belonging to old age or aged persons; gerontological; geriatric. |
| 3. | Physical Geography. (of topographical features) having been reduced by erosion to a featureless plain that stands everywhere at base level. Compare peneplain. |
| 4. | a senile person. |
senile se·nile (sē'nīl', sěn'īl')
adj.
Relating to, characteristic of, or resulting from old age.
Exhibiting the symptoms of senility, as impaired memory or the inability to perform certain mental tasks.