A substance added to cause improvement (especially to a foodstuff)(noun)
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Use "improver" in a sentence
"My favorite society-improver is Compassion International. kujoko at att dot net"
"The inventive field is large, and each invention opens up a new field for improvements, and it is the "improver," without question, that reaps the greatest benefit from any invention."
"The motive that shears the trees also razes the copse, in order that the gardener or "improver" may show his art."