diff --git a/src/lib/locale/en.js b/src/lib/locale/en.js
index ef95f1796c..33b1c4b32c 100644
--- a/src/lib/locale/en.js
+++ b/src/lib/locale/en.js
@@ -8,9 +8,9 @@ getSetGlobalLocale('en', {
             since:  '0001-01-01',
             until:  +Infinity,
             offset: 1,
-            name:   'After Christ',
-            narrow: 'AC',
-            abbr:   'AC'
+            name:   'Anno Domini',
+            narrow: 'AD',
+            abbr:   'AD'
         },
         {
             since:  '0000-12-31',
diff --git a/src/locale/ja.js b/src/locale/ja.js
index 91d61e7ed7..c7bb682310 100644
--- a/src/locale/ja.js
+++ b/src/locale/ja.js
@@ -42,8 +42,8 @@ export default moment.defineLocale('ja', {
             until:  '1873-12-31',
             offset: 1,
             name:   '西暦',
-            narrow: 'AC',
-            abbr:   'AC'
+            narrow: 'AD',
+            abbr:   'AD'
         },
         {
             since:  '0000-12-31',
diff --git a/src/test/locale/en.js b/src/test/locale/en.js
index 169090fd00..56e0aadf64 100644
--- a/src/test/locale/en.js
+++ b/src/test/locale/en.js
@@ -59,14 +59,14 @@ test('format', function (assert) {
 });
 
 test('parse era', function (assert) {
-    assert.equal(moment('2010 AC', 'y N', true).isValid(), true, '2010 AC');
-    assert.equal(moment('2010 AC', 'y N', true).year(),    2010, '2010 AC');
+    assert.equal(moment('2010 AD', 'y N', true).isValid(), true, '2010 AD');
+    assert.equal(moment('2010 AD', 'y N', true).year(),    2010, '2010 AD');
 
-    assert.equal(moment('2010 After Christ', 'y N', true).isValid(), false, '2010 After Christ');
-    assert.equal(moment('2010 After Christ', 'y N', false).isValid(), true, '2010 After Christ');
-    assert.equal(moment('2010 After Christ', 'y NNNN', true).isValid(), true, '2010 After Christ');
-    assert.equal(moment('2010 After Christ', 'y NNNN', true).year(), 2010, '2010 After Christ');
-    assert.equal(moment('2010 After Christ', 'y N', false).year(), 2010, '2010 After Christ');
+    assert.equal(moment('2010 Anno Domini', 'y N', true).isValid(), false, '2010 Anno Domini');
+    assert.equal(moment('2010 Anno Domini', 'y N', false).isValid(), true, '2010 Anno Domini');
+    assert.equal(moment('2010 Anno Domini', 'y NNNN', true).isValid(), true, '2010 Anno Domini');
+    assert.equal(moment('2010 Anno Domini', 'y NNNN', true).year(), 2010, '2010 Anno Domini');
+    assert.equal(moment('2010 Anno Domini', 'y N', false).year(), 2010, '2010 Anno Domini');
 
     assert.equal(moment('469 BC', 'y N', true).isValid(), true, '469 BC');
     assert.equal(moment('469 BC', 'y N', true).year(), -468, '469 BC');
@@ -77,9 +77,9 @@ test('parse era', function (assert) {
 
 test('format era', function (assert) {
     var a = [
-            ['+000001-01-01', 'N, NN, NNN',     'AC, AC, AC'],
-            ['+000001-01-01', 'NNNN',           'After Christ'],
-            ['+000001-01-01', 'NNNNN',          'AC'],
+            ['+000001-01-01', 'N, NN, NNN',     'AD, AD, AD'],
+            ['+000001-01-01', 'NNNN',           'Anno Domini'],
+            ['+000001-01-01', 'NNNNN',          'AD'],
             ['+000001-01-01', 'y',              '1'],
 
             ['+000000-12-31', 'N, NN, NNN',     'BC, BC, BC'],
diff --git a/src/test/locale/ja.js b/src/test/locale/ja.js
index a2d82606bc..a30181d709 100644
--- a/src/test/locale/ja.js
+++ b/src/test/locale/ja.js
@@ -142,15 +142,15 @@ test('format era', function (assert) {
             ['+001873-01-01', 'yo',             '6年'],
 
             /* Christinan Era */
-            ['+001872-12-31', 'N, NN, NNN',     'AC, AC, AC'],
+            ['+001872-12-31', 'N, NN, NNN',     'AD, AD, AD'],
             ['+001872-12-31', 'NNNN',           '西暦'],
-            ['+001872-12-31', 'NNNNN',          'AC'],
+            ['+001872-12-31', 'NNNNN',          'AD'],
             ['+001872-12-31', 'y yy yyy yyyy',  '1872 1872 1872 1872'],
             ['+001872-12-31', 'yo',             '1872年'],
 
-            ['+000001-01-01', 'N, NN, NNN',     'AC, AC, AC'],
+            ['+000001-01-01', 'N, NN, NNN',     'AD, AD, AD'],
             ['+000001-01-01', 'NNNN',           '西暦'],
-            ['+000001-01-01', 'NNNNN',          'AC'],
+            ['+000001-01-01', 'NNNNN',          'AD'],
             ['+000001-01-01', 'y',              '1'],
 
             ['+000000-12-31', 'N, NN, NNN',     'BC, BC, BC'],