loss of a large block of interrelated memories; complete or partial loss of memory caused by brain injury, shock, etc.
Origin: 1780–90; < NL < Gk amnēsía, var. of amnēstía oblivion; perhaps learnedly formed from mnē-, s. of mimnskesthai to remember (cf. mnemonic) + -s- + -ia-ia.See amnesty
am·ne·sia (ām-nē'zhə) n. Partial or total loss of memory, usually resulting from shock, psychological disturbance, brain injury, or illness.
[Greek amnēsiā, forgetfulness, probably from amnēstiā, from amnēstos, not remembered : a-, not; see a-1 + mimnēskein, mnē-, to remember; see men-1 in Indo-European roots.] am·ne'si·ac' (-nē'zē-āk', -zhē-āk'), am·ne'sic (-zĭk, -sĭk) n. & adj., am·nes'tic (-něs'tĭk) adj.