Try \renewtheorem{theorem}{... the french word ...}
Thanks, Herbert. But, where should I insert that command?
In the preamble. Layout->Document->Preamble
I did it, but I get the following error message:
LaTeX Error: Missing \begin{document}. \renewtheorem{t heorem}{FrenchTheorem} You're in trouble here. Try typing <return> to proceed. If that doesn't work, type X <return> to quit.
please send a testfile
Herbert
