agnosia
noun
ag·no·sia ag-ˈnō-zhə 
-shə
: loss or diminution of the ability to recognize familiar objects or stimuli usually as a result of brain damage
Word History
Etymology
borrowed from German Agnosie, borrowed from Greek agnōsía "lack of knowledge, ignorance," from a- a- entry 2 + -gnōsia (from gnôsis "knowledge" + -ia -ia entry 1) — more at gnosis
First Known Use
1883, in the meaning defined above
Medical Definition
agnosia
noun
ag·no·sia ag-ˈnō-zhə -shə
-shə : loss or diminution of the ability to recognize familiar objects or stimuli usually as a result of brain damage see visual agnosia