purge (v.) Look up purge at Dictionary.com
c. 1300, "clear of a charge or suspicion;" late 14c., "cleanse, clear, purify," from Anglo-French purger, Old French purgier "wash, clean; refine, purify" morally or physically (12c., Modern French purger) and directly from Latin purgare "cleanse, make clean; purify," especially of the body, "free from what is superfluous; remove, clear away," figuratively "refute, justify, vindicate" (also source of Spanish purgar, Italian purgare), from Old Latin purigare, from purus "pure" (see pure) + root of agere "to drive, make" (see act (n.)). Related: Purged; purging.
purge (n.) Look up purge at Dictionary.com
1560s, "that which purges," from purge (v.). Meaning "a purgative, an act of purging" is from 1590s. Political sense from 1730. Earliest sense in English was the now-obsolete one "examination in a legal court" (mid-15c.).