diff --git a/01.curriculum/01.physics-chemistry-biology/04.Niv4/04.electromagnetism/02.electromagnetic-waves-vacuum/02.electromagnetic-waves-vacuum-main/textbook.fr.md b/01.curriculum/01.physics-chemistry-biology/04.Niv4/04.electromagnetism/02.electromagnetic-waves-vacuum/02.electromagnetic-waves-vacuum-main/textbook.fr.md
index 06adbee9d..e58582895 100644
--- a/01.curriculum/01.physics-chemistry-biology/04.Niv4/04.electromagnetism/02.electromagnetic-waves-vacuum/02.electromagnetic-waves-vacuum-main/textbook.fr.md
+++ b/01.curriculum/01.physics-chemistry-biology/04.Niv4/04.electromagnetism/02.electromagnetic-waves-vacuum/02.electromagnetic-waves-vacuum-main/textbook.fr.md
@@ -310,7 +310,7 @@ Propriétés de l'onde EM plane progressive monochromatique dans le vide :
 
 * **$`\overrightarrow{k}\land\overrightarrow{E}=\omega\overrightarrow{B}`$**
 
-$`\hspace{0.6cm}\Longrightarrow`$ l'OPP EM est transverse.
+$`\hspace{0.6cm}\Longrightarrow`$ l'OPPM EM est transverse.
 
 $`\hspace{0.6cm}\Longrightarrow (\overrightarrow{k},\overrightarrow{E},\overrightarrow{B})`$ forment un trièdre direct.