#1 melioration n. [amelioration, betterment] the act of relieving ills and changing for the better. wn
#2 melioration n. [improvement] a condition superior to an earlier condition; "the new school represents a great improvement". wn
#3 melioration n. the linguistic process in which over a period of time a word grows more positive in connotation or more elevated in meaning. wn
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