Definition of caustic
(Entry 1 of 2)
2 : marked by incisive sarcasm
a caustic film review caustic humor
3 : relating to or being the surface or curve of a caustic (see caustic entry 2 sense 2)
caustic
nounDefinition of caustic (Entry 2 of 2)
1 : a caustic agent: such as
a : a substance that burns or destroys organic tissue by chemical action
b : a strong corrosive alkali (such as sodium hydroxide)
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Time Traveler for caustic
The first known use of caustic was in the 14th century
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