n. pl. cat·a·plex·ies
A sudden loss of muscle tone and strength, usually caused by an extreme emotional stimulus.
[From Greek kataplēxis, fixation (of the eyes), from kataplēssein, to astound, terrify : kata-, intensive pref.; see CATA- + plēssein, plēk-, to strike; see plāk-2 in the Appendix of Indo-European roots.]
cat′a·plectic (-plĕktĭk) adj.
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