"Their eggs were addled." William Cowper.
The elderly who do difficult tasks that fluster them is an example of addle.
Milk that has gone bad without refrigeration is an example of addle.
An example of addle is a person who has amnesia and who isn't sure where he is.
Origin of addle
- From Middle English adel rotten from Old English adel pool of excrement
From American Heritage Dictionary of the English Language, 5th Edition
- From Middle English addlen, from Old English edlēan (“reward, pay-back”), edlēanian (“to reward, recompense”); or of North Germanic origin, from Old Norse ǫðlask (“to gain possession of property”), from ōðal (“owndom, property”).