diff --git a/light/light.c b/light/light.c
index 98cb1f92..6a591b2a 100644
--- a/light/light.c
+++ b/light/light.c
@@ -279,7 +279,7 @@ main(int argc, const char **argv)
 		anglescale = sun_anglescale = atoi(argv[++i]);
 	    else
 		Error("-anglesense requires a numeric argument (0.0 - 1.0)");
-	} else if ( !strcmp( argv[ i ], "-dirty" ) ) {
+	} else if ( !strcmp( argv[ i ], "-dirt" ) || !strcmp( argv[ i ], "-dirty" ) ) {
 	    dirty = true;
 	    globalDirt = true;
 	    minlightDirt = true;
@@ -335,7 +335,7 @@ main(int argc, const char **argv)
 	printf("usage: light [-threads num] [-extra|-extra4]\n"
 	       "             [-light num] [-addmin] [-anglescale|-anglesense]\n"
 	       "             [-dist n] [-range n] [-gate n] [-lit]\n"
-	       "             [-dirty] [-dirtdebug] [-dirtmode n] [-dirtdepth n] [-dirtscale n] [-dirtgain n]\n"
+	       "             [-dirt] [-dirtdebug] [-dirtmode n] [-dirtdepth n] [-dirtscale n] [-dirtgain n]\n"
 	       "             [-soft [n]] [-fence] bspfile\n");
 	exit(1);
     }
diff --git a/man/light.1 b/man/light.1
index 782abfd1..0cf2dcff 100644
--- a/man/light.1
+++ b/man/light.1
@@ -59,11 +59,11 @@ surface (more detailed explanation in the "_anglescale" key below).
 Force generation of a .lit file, even if your map does not have any coloured
 lights. By default, light will automatically generate the .lit file when
 needed.
-.IP "\fB\-dirty\fP"
+.IP "\fB\-dirt\fP"
 Globally enables dirtmapping (ambient occlusion), overriding the "_dirt" worldspawn
 key. See "_dirt" for more details.
 .IP "\fB\-dirtdebug\fP"
-Implies "-dirty", and renders just the dirtmap against a fullbright background,
+Implies "-dirt", and renders just the dirtmap against a fullbright background,
 ignoring all lights in the map. Useful for previewing and turning the dirt settings.
 .IP "\fB\-dirtmode n\fP | \fB\-dirtdepth n\fP | \fB\-dirtscale n\fP | \fB\-dirtgain n\fP"
 Fine-tune the dirtmapping, overriding the corresponding worldspawn keys. See the