diff --git a/Source/HBIOS/hbios.asm b/Source/HBIOS/hbios.asm
index 2effdae7..5f2304e8 100644
--- a/Source/HBIOS/hbios.asm
+++ b/Source/HBIOS/hbios.asm
@@ -8802,7 +8802,6 @@ PS_SDLPT	.TEXT	"LPT$"
 PS_SDESPCON	.TEXT	"ESPCON$"
 PS_SDESPSER	.TEXT	"ESPSER$"
 PS_SDSCON	.TEXT	"SCON$"
-PS_SDEF		.TEXT	"EF$"
 PS_SDSSER	.TEXT	"SSER$"
 PS_SDEZ80	.TEXT	"EZ80$"
 ;