diff --git a/lang/ja.json b/lang/ja.json
index 4b7cc8a..15f71d2 100644
--- a/lang/ja.json
+++ b/lang/ja.json
@@ -7,7 +7,7 @@
     "category:benches": "",
     "category:buildings": "建物",
     "category:buildings-entrances": "エントランス",
-    "category:buildings-figure-ground": "",
+    "category:buildings-figure-ground": "フィギュア-グランド図式",
     "category:buildings-height": "建物の高さ",
     "category:buildings-start_date": "築年数",
     "category:buildings-type": "建物の種類",
@@ -16,7 +16,7 @@
     "category:car_maxspeed": "最高速度",
     "category:car_routes": "車のルート",
     "category:children": "子ども用施設",
-    "category:climbing": "",
+    "category:climbing": "登山",
     "category:coal": "石炭",
     "category:communication": "情報通信",
     "category:construction": "工事中",
@@ -36,13 +36,13 @@
     "category:health": "健康",
     "category:hiking_routes": "ハイキングルート",
     "category:historic": "歴史",
-    "category:index": "",
+    "category:index": "目次(カテゴリ)",
     "category:infrastructure": "インフラ",
     "category:internet": "インターネット接続",
     "category:law": "法律",
     "category:leisure": "レジャー",
     "category:leisure_sport_shopping": "レジャー",
-    "category:memorial": "記念碑",
+    "category:memorial": "記念碑&記念建造物",
     "category:military": "軍事",
     "category:mtb-routes": "マウンテンバイクのルート",
     "category:natural": "自然地層",
@@ -65,15 +65,15 @@
     "category:public": "公共サービス",
     "category:railway": "鉄道",
     "category:railway-electrification": "鉄道の電力",
-    "category:railway-gauge": "",
+    "category:railway-gauge": "軌間",
     "category:railway-infrastructure": "鉄道インフラ",
     "category:railway-maxspeed": "鉄道の最高速度",
     "category:railway-routes": "鉄道ルート",
     "category:religion": "宗教",
-    "category:renewables": "",
+    "category:renewables": "再生可能エネルギー",
     "category:residential": "住居エリア",
-    "category:resources": "",
-    "category:roads": "",
+    "category:resources": "資源採集",
+    "category:roads": "道路",
     "category:services": "サービス",
     "category:shop": "ショッピング",
     "category:special": "特別",
@@ -93,7 +93,7 @@
     "category:wikipedia": "ウィキペディア",
     "category:works": "工場",
     "category:xmas": "クリスマス",
-    "date format not understood": "",
-    "outdated feature": "",
+    "date format not understood": "日付形式が正しくありません",
+    "outdated feature": "期間外",
     "xmas:outdated-warning": "今のシーズンは地物が更新されていません! チェックして現在の日付に'xmas:lastcheck' タグをセットしてください。"
 }