#1 lessen v. [decrease, diminish, fall] decrease in size, extent, or range; "The amount of homework decreased towards the end of the semester"; "The cabin pressure fell dramatically"; "her weight fell to under a hundred pounds"; "his voice fell to a whisper". wn
#2 lessen v. [decrease, minify] make smaller; "He decreased his staff". wn
#3 lessen v. [subside] wear off or die down; "The pain subsided". wn
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