diff --git a/locale/update_po_files.sh b/locale/update_po_files.sh
index 143c548bf..7ded141d0 100755
--- a/locale/update_po_files.sh
+++ b/locale/update_po_files.sh
@@ -5,7 +5,7 @@ sed -E 's/\.\.\///g' |\
 xargs xgettext \
 --default-domain=audacity \
 --directory=.. \
---keyword=_ --keyword=XO --keyword=XXO --keyword=XP:1,2 \
+--keyword=_ --keyword=XO --keyword=XC:1,2c --keyword=XXO --keyword=XP:1,2 --keyword=XPC:1,2,4c \
 --add-comments=" i18n" \
 --add-location=file  \
 --copyright-holder='Audacity Team' \
@@ -19,7 +19,7 @@ sed -E 's/\.\.\///g' |\
 xargs xgettext \
 --default-domain=audacity \
 --directory=.. \
---keyword=_ --keyword=ngettext:1,2 \
+--keyword=_ --keyword=_C:1,2c --keyword=ngettext:1,2 --keyword=ngettextc:1,2,4c \
 --add-comments=" i18n" \
 --add-location=file  \
 --copyright-holder='Audacity Team' \
diff --git a/src/Internat.cpp b/src/Internat.cpp
index 8eb1d8cc1..b92054507 100644
--- a/src/Internat.cpp
+++ b/src/Internat.cpp
@@ -363,7 +363,7 @@ wxString TranslatableString::DoChooseFormat(
       ? ( nn == 1 ? singular : plural )
       : wxGetTranslation(
             singular, plural, nn
-#if wxCHECK_VERSION(3, 1, 3)
+#if HAS_I18N_CONTEXTS
             , wxString{} // domain
             , context
 #endif
diff --git a/src/Internat.h b/src/Internat.h
index a6aa0b26a..31f529c81 100644
--- a/src/Internat.h
+++ b/src/Internat.h
@@ -32,7 +32,13 @@ extern AUDACITY_DLL_API const wxString& GetCustomSubstitution(const wxString& st
 // '&', preceding menu accelerators, should NOT occur in the argument.
 #define XO(s)  (TranslatableString{ wxT(s), {} })
 
-// Marks strings for extraction only, where '&', preceding men accelerators, MAY
+// Alternative taking a second context argument.  A context is a string literal,
+// which is not translated, but serves to disambiguate uses of the first string
+// that might need differing translations, such as "Light" meaning not-heavy in
+// one place but not-dark elsewhere.
+#define XC(s, c)  (TranslatableString{ wxT(s), {} }.Context(c))
+
+// Marks strings for extraction only, where '&', preceding menu accelerators, MAY
 // occur.
 // For now, expands exactly as macro XO does, but in future there will be a
 // type distinction - for example XXO should be used for menu item names that
@@ -86,6 +92,10 @@ extern AUDACITY_DLL_API const wxString& GetCustomSubstitution(const wxString& st
 #define XP(sing, plur, n) \
    TranslatableString{ wxT(sing), {} }.Plural<(n)>( wxT(plur) )
 
+// Like XP but with an additional context argument, as for XC
+#define XPC(sing, plur, n, c) \
+   TranslatableString{ wxT(sing), {} }.Context(c).Plural<(n)>( wxT(plur) )
+
 #endif
 
 class Internat
@@ -151,4 +161,9 @@ TranslatableStrings Msgids(
    const EnumValueSymbol strings[], size_t nStrings);
 TranslatableStrings Msgids( const std::vector<EnumValueSymbol> &strings );
 
+// Whether disambiguationg contexts are supported
+// If not, then the program builds and runs, but strings in the catalog with
+// contexts will fail to translate
+#define HAS_I18N_CONTEXTS wxCHECK_VERSION(3, 1, 1)
+
 #endif
diff --git a/src/PluginManager.cpp b/src/PluginManager.cpp
index a05e2842d..bae6be3ec 100644
--- a/src/PluginManager.cpp
+++ b/src/PluginManager.cpp
@@ -1897,10 +1897,13 @@ bool PluginManager::DropFile(const wxString &fileName)
 
             // Ask whether to enable the plug-ins
             if (auto nIds = ids.size()) {
-               auto message = XP(
+               auto message = XPC(
+               /* i18n-hint A plug-in is an optional added program for a sound
+                effect, or generator, or analyzer */
                   "Enable this plug-in?\n",
                   "Enable these plug-ins?\n",
-                  0
+                  0,
+                  "plug-ins"
                )( nIds );
                for (const auto &name : names)
                   message.Join( Verbatim( name ), wxT("\n") );
diff --git a/src/commands/ScreenshotCommand.cpp b/src/commands/ScreenshotCommand.cpp
index f28b34901..ac8e98307 100644
--- a/src/commands/ScreenshotCommand.cpp
+++ b/src/commands/ScreenshotCommand.cpp
@@ -94,7 +94,8 @@ kBackgroundStrings[ ScreenshotCommand::nBackgrounds ] =
 {
    // These are acceptable dual purpose internal/visible names
    { XO("Blue") },
-   { XO("White") },
+   /* i18n-hint:  This really means the color, not as in "white noise" */
+   { XC("White", "color") },
    { XO("None") },
 };
 
diff --git a/src/effects/Noise.cpp b/src/effects/Noise.cpp
index b27698e7b..fdf4ce665 100644
--- a/src/effects/Noise.cpp
+++ b/src/effects/Noise.cpp
@@ -41,9 +41,13 @@ enum kTypes
 static const EnumValueSymbol kTypeStrings[nTypes] =
 {
    // These are acceptable dual purpose internal/visible names
-   { XO("White") },
-   { XO("Pink") },
-   { XO("Brownian") }
+   /* i18n-hint: not a color, but "white noise" having a uniform spectrum  */
+   { XC("White", "noise") },
+   /* i18n-hint: not a color, but "pink noise" having a spectrum with more power
+    in low frequencies */
+   { XC("Pink", "noise") },
+   /* i18n-hint: a kind of noise spectrum also known as "red" or "brown" */
+   { XC("Brownian", "noise") }
 };
 
 // Define keys, defaults, minimums, and maximums for the effect parameters
diff --git a/src/effects/nyquist/Nyquist.cpp b/src/effects/nyquist/Nyquist.cpp
index e11af3c8a..c692d9c24 100644
--- a/src/effects/nyquist/Nyquist.cpp
+++ b/src/effects/nyquist/Nyquist.cpp
@@ -1443,8 +1443,8 @@ bool NyquistEffect::ProcessOne()
 
    if (rval == nyx_string) {
       // Assume the string has already been translated within the Lisp runtime
-      // if necessary, by gettext or ngettext defined below, before it is
-      // communicated back to C++
+      // if necessary, by one of the gettext functions defined below, before it
+      // is communicated back to C++
       auto msg = Verbatim( NyquistToWxString(nyx_get_string()) );
       if (!msg.empty()) { // Empty string may be used as a No-Op return value.
          Effect::MessageBox( msg );
@@ -3332,20 +3332,58 @@ void NyquistOutputDialog::OnOk(wxCommandEvent & /* event */)
 static LVAL gettext()
 {
    auto string = UTF8CTOWX(getstring(xlgastring()));
+#if !HAS_I18N_CONTEXTS
+   // allow ignored context argument
+   if ( moreargs() )
+      nextarg();
+#endif
    xllastarg();
    return cvstring(GetCustomTranslation(string).mb_str(wxConvUTF8));
 }
 
+static LVAL gettextc()
+{
+#if HAS_I18N_CONTEXTS
+   auto string = UTF8CTOWX(getstring(xlgastring()));
+   auto context = UTF8CTOWX(getstring(xlgastring()));
+   xllastarg();
+   return cvstring(wxGetTranslation( string, "", 0, "", context )
+      .mb_str(wxConvUTF8));
+#else
+   return gettext();
+#endif
+}
+
 static LVAL ngettext()
 {
    auto string1 = UTF8CTOWX(getstring(xlgastring()));
    auto string2 = UTF8CTOWX(getstring(xlgastring()));
    auto number = getfixnum(xlgafixnum());
+#if !HAS_I18N_CONTEXTS
+   // allow ignored context argument
+   if ( moreargs() )
+      nextarg();
+#endif
    xllastarg();
    return cvstring(
       wxGetTranslation(string1, string2, number).mb_str(wxConvUTF8));
 }
 
+static LVAL ngettextc()
+{
+#if HAS_I18N_CONTEXTS
+   auto string1 = UTF8CTOWX(getstring(xlgastring()));
+   auto string2 = UTF8CTOWX(getstring(xlgastring()));
+   auto number = getfixnum(xlgafixnum());
+   auto context = UTF8CTOWX(getstring(xlgastring()));
+   xllastarg();
+   return cvstring(wxGetTranslation( string1, string2, number, "", context )
+      .mb_str(wxConvUTF8));
+#else
+   return ngettext();
+#endif
+}
+
 /*--------------------Audacity Automation -------------------------*/
 /* These functions may later move to their own source file. */
 extern void * ExecForLisp( char * pIn );
@@ -3413,8 +3451,9 @@ static void RegisterFunctions()
       // All function names must be UP-CASED
       static const FUNDEF functions[] = {
          { "_", SUBR, gettext },
-         // to do: more i18n functions, for contexts and plurals
+         { "_C", SUBR, gettextc },
          { "NGETTEXT", SUBR, ngettext },
+         { "NGETTEXTC", SUBR, ngettextc },
          { "AUD-DO",  SUBR, xlc_aud_do },
        };