tr.v. de·ranged, de·rang·ing, de·rang·es
1. To disturb the order, arrangement, or functioning of: an asteroid impact large enough to derange the climate.
2. To upset (normal condition or functioning, as of a bodily organ).
3. To cause to be psychotic or otherwise severely mentally unsound.
[French déranger, from Old French desrengier : des-, de- + reng, line (of Germanic origin; see sker-2 in the Appendix of Indo-European roots).]
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