Six-Letter Words

My National Review Online "Diary" column for August 2003 included a non-mathematical brainteaser that I filched from Hilaire Belloc:   

Two Six-Letter Words

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Two six-letter words, one English and one French, have precisely the same meaning and are directly descended from the same Latin root; yet they have not a single letter in common.  No letter that appears in the English word can be found in the French one, and vice versa.  What are the two words?  

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First of all, I confess to having made a total pig's ear out of the question statement.  The last three words of the second sentence are redundant; and although the two mystery words are indeed derived from a single Latin root, that root itself derives directly from Greek, and I suppose I should have said so.

All that aside, the two words are "bishop" and "évêque," which both derive from Latin "episcopus."