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dementia vs. senility

[dih-men-shuh, -shee-uh] / dɪˈmɛn ʃə, -ʃi ə /

noun

  1. a condition characterized by progressive, persistent, severe impairment of intellectual capacity, including memory loss, confusion, and emotional instability, resulting from the loss of or damage to neurons in the brain.

[si-nil-i-tee] / sɪˈnɪl ɪ ti /

noun

  1. the state of being senile, especially the weakness or mental infirmity of old age.