diff --git a/specs/udmf_zdoom.txt b/specs/udmf_zdoom.txt
index 402f3d6e8..73e94ea8a 100644
--- a/specs/udmf_zdoom.txt
+++ b/specs/udmf_zdoom.txt
@@ -424,7 +424,7 @@ Note: All <bool> fields default to false unless mentioned otherwise.
 
       lm_sampledist = <int>;        // ZDRay lightmap sample distance for the entire map. Defines the map units each lightmap texel covers. Must be in powers of two. Default = 8
       lm_suncolor = <string>;       // ZDRay lightmap sun color in hex. Default = "FFFFFF"
-      SourceRadius = <float>;       // ZDRay lightmap light and raytraced dynamic light soft shadow amount. Higher values produce softer shadows. Default = 5.0
+      SoftShadowRadius = <float>;   // ZDRay lightmap light and raytraced dynamic light soft shadow amount. Higher values produce softer shadows. Default = 5.0
 
       friendlyseeblocks = <int>;    // How far (in block units) a friendly monster can see other monsters. Default 10
 
diff --git a/src/namedef_custom.h b/src/namedef_custom.h
index e04dc3795..61bf9d261 100644
--- a/src/namedef_custom.h
+++ b/src/namedef_custom.h
@@ -865,7 +865,7 @@ xx(lm_suncolor)
 xx(lm_sampledist)
 
 // Light keywords
-xx(SourceRadius)
+xx(SoftShadowRadius)
 
 xx(skew_bottom_type)
 xx(skew_middle_type)