dotard

名词 dotard:

1. an oldster in his dotage; someone whose age has impaired his intellect

dot.ard

n.（名词）
A person who is in his or her dotage.
年老昏聩的人：处于他（她）衰老阶段的人

来源：
Middle English
中古英语
from doten [to dote]
源自 doten [昏聩]