diff --git a/IPython/html/static/notebook/js/kernelselector.js b/IPython/html/static/notebook/js/kernelselector.js
index 18b016f..cdc3f5e 100644
--- a/IPython/html/static/notebook/js/kernelselector.js
+++ b/IPython/html/static/notebook/js/kernelselector.js
@@ -164,7 +164,7 @@ define([
         /** set the kernel by name, ensuring kernelspecs have been loaded, first 
         
         kernel can be just a kernel name, or a notebook kernelspec metadata
-        (name, language_name, display_name).
+        (name, language, display_name).
         */
         var that = this;
         if (typeof selected === 'string') {
@@ -192,9 +192,9 @@ define([
         if (ks === undefined) {
             var available = _sorted_names(kernelspecs);
             var matches = [];
-            if (selected.language_name && selected.language_name.length > 0) {
+            if (selected.language && selected.language.length > 0) {
                 $.map(available, function (name) {
-                    if (kernelspecs[name].spec.language_name.toLowerCase() === selected.language_name.toLowerCase()) {
+                    if (kernelspecs[name].spec.language.toLowerCase() === selected.language.toLowerCase()) {
                         matches.push(name);
                     }
                 });
diff --git a/IPython/html/static/notebook/js/notebook.js b/IPython/html/static/notebook/js/notebook.js
index 7a9ad3b..49684a6 100644
--- a/IPython/html/static/notebook/js/notebook.js
+++ b/IPython/html/static/notebook/js/notebook.js
@@ -249,7 +249,7 @@ define([
             that.metadata.kernelspec = {
                 name: data.name,
                 display_name: data.spec.display_name,
-                language_name: data.spec.language_name,
+                language: data.spec.language,
             };
             // start session if the current session isn't already correct
             if (!(this.session && this.session.kernel && this.session.kernel.name === data.name)) {
diff --git a/IPython/kernel/kernelspec.py b/IPython/kernel/kernelspec.py
index 2934ea4..5e73238 100644
--- a/IPython/kernel/kernelspec.py
+++ b/IPython/kernel/kernelspec.py
@@ -36,7 +36,7 @@ def _pythonfirst(s):
 class KernelSpec(HasTraits):
     argv = List()
     display_name = Unicode()
-    language_name = Unicode()
+    language = Unicode()
     env = Dict()
     resource_dir = Unicode()
     
@@ -55,7 +55,7 @@ class KernelSpec(HasTraits):
         d = dict(argv=self.argv,
                  env=self.env,
                  display_name=self.display_name,
-                 language_name=self.language_name,
+                 language=self.language,
                 )
 
         return d
@@ -114,7 +114,7 @@ class KernelSpecManager(HasTraits):
         return {
                 'argv': make_ipkernel_cmd(),
                 'display_name': 'Python %i' % (3 if PY3 else 2),
-                'language_name': 'python',
+                'language': 'python',
                }
 
     @property