diff --git a/NmapOps.h b/NmapOps.h
index 9bc5ea05e..9f44aa8b8 100644
--- a/NmapOps.h
+++ b/NmapOps.h
@@ -244,7 +244,7 @@ class NmapOps {
 
   int max_ips_to_scan; // Used for Random input (-iR) to specify how 
                        // many IPs to try before stopping. 0 means unlimited.
-  int extra_payload_length; /* These two are for --data_length op */
+  int extra_payload_length; /* These two are for --data-length op */
   char *extra_payload;
   unsigned long host_timeout;
   /* Delay between probes, in milliseconds */
diff --git a/docs/refguide.xml b/docs/refguide.xml
index 91d84e8c0..1573052fa 100644
--- a/docs/refguide.xml
+++ b/docs/refguide.xml
@@ -3323,8 +3323,8 @@ overwhelming requests.  Specify <option>--open</option> to only see
 
       <varlistentry>
         <term>
-          <option>--no_stylesheet</option> (Omit XSL stylesheet declaration from XML)
-          <indexterm><primary>--no_stylesheet</primary></indexterm>
+          <option>--no-stylesheet</option> (Omit XSL stylesheet declaration from XML)
+          <indexterm><primary>--no-stylesheet</primary></indexterm>
         </term>
         <listitem>
 
diff --git a/idle_scan.cc b/idle_scan.cc
index 3f442c291..8b10e9ad6 100644
--- a/idle_scan.cc
+++ b/idle_scan.cc
@@ -132,7 +132,7 @@ struct idle_proxy_info {
   u16 probe_port; /* The port we use for probing IP ID infoz */
   u16 max_groupsz; /* We won't test groups larger than this ... */
   u16 min_groupsz; /* We won't allow the group size to fall below this
-		      level.  Affected by --min_parallelism */
+		      level.  Affected by --min-parallelism */
   double current_groupsz; /* Current group size being used ... depends on
                           conditions ... won't be higher than
                           max_groupsz */
diff --git a/nmap_dns.cc b/nmap_dns.cc
index ce7b4af6b..05552807e 100644
--- a/nmap_dns.cc
+++ b/nmap_dns.cc
@@ -1164,7 +1164,7 @@ static void nmap_mass_rdns_core(Target **targets, int num_targets) {
     if (o.dns_servers) add_dns_server(o.dns_servers);
     else parse_resolvdotconf();
 
-    if (servs.size() == 0 && firstrun) error("mass_dns: warning: Unable to determine any DNS servers. Reverse DNS is disabled. Try using --system-dns or specify valid servers with --dns_servers");
+    if (servs.size() == 0 && firstrun) error("mass_dns: warning: Unable to determine any DNS servers. Reverse DNS is disabled. Try using --system-dns or specify valid servers with --dns-servers");
   }
 
 
diff --git a/tcpip.h b/tcpip.h
index c5af557f9..49be4310c 100644
--- a/tcpip.h
+++ b/tcpip.h
@@ -232,7 +232,7 @@ typedef enum { devt_ethernet, devt_loopback, devt_p2p, devt_other  } devtype;
 
 
 /* Used for tracing all packets sent or received (eg the
-   --packet_trace option) */
+   --packet-trace option) */
 class PacketTrace {
  public:
   /*  static const int SEND=1;