Duplicity is defined as deception or a lie.(noun)
An example of duplicity is when a person has pretended to be someone who he is not.
See duplicity in Webster's New World College Dictionary
noun pl. duplicities
Origin: ME duplicite < OFr duplicité < LL duplicitas < L duplicare: see duplex
See duplicity in American Heritage Dictionary 4
noun pl. du·plic·i·ties
Origin: Middle English duplicite
Origin: , from Old French
Origin: , from Late Latin duplicitās, doubleness
Origin: , from Latin duplex, duplic-, twofold; see dwo- in Indo-European roots.
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