Emily Dickinson Lexicon

DU-PLIC'I-TY, n. [Fr. duplicité; Sp. duplicidad; It. duplicità; from L. duplex, double.]

1. Doubleness; the number two. – Watts.
2. Doubleness of heart or speech; the act or practice of exhibiting a different or contrary conduct, or uttering different or contrary sentiments, at different times, in relation to the same thing; or the act of dissembling one's real opinions for the purpose of concealing them and misleading persons in the conversation and intercourse of life; double-dealing; dissimulation; deceit.
3. In law, duplicity is the pleading of two or more distinct matters or single pleas. – Blackstone.