The definition of caustic is a substance that burns or eats away by chemical reaction or a hurtful remark or relationship.(adjective)
See caustic in Webster's New World College Dictionary
Origin: ME caustik < L causticus < Gr kaustikos < kaustos, burning < kaiein, to burn
Origin: L causticum < the adj.
See caustic in American Heritage Dictionary 4
Origin: Middle English caustik
Origin: , from Latin causticus
Origin: , from Greek kaustikos
Origin: , from kaustos
Origin: , from kaiein, kau-, to burn.
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