diff --git a/src/main/java/de/komoot/photon/App.java b/src/main/java/de/komoot/photon/App.java
index 3ba382da4..33868a6c3 100644
--- a/src/main/java/de/komoot/photon/App.java
+++ b/src/main/java/de/komoot/photon/App.java
@@ -65,7 +65,7 @@ public static void main(String[] rawArgs) throws Exception {
 
             // Working on an existing installation.
             // Update the index settings in case there are any changes.
-            esServer.updateIndexSettings();
+            esServer.updateIndexSettings(args.getSynonymFile());
             esClient.admin().cluster().prepareHealth().setWaitForYellowStatus().get();
 
             if (args.isNominatimUpdate()) {
diff --git a/src/main/java/de/komoot/photon/CommandLineArgs.java b/src/main/java/de/komoot/photon/CommandLineArgs.java
index d7a7bb6f5..9fd3ed453 100644
--- a/src/main/java/de/komoot/photon/CommandLineArgs.java
+++ b/src/main/java/de/komoot/photon/CommandLineArgs.java
@@ -35,6 +35,9 @@ public class CommandLineArgs {
     @Parameter(names = "-extra-tags", description = "additional tags to save for each place")
     private String extraTags = "";
 
+    @Parameter(names = "-synonym-file", description = "list of synonyms to apply at query time")
+    private  String synonymFile = null;
+
     @Parameter(names = "-json", description = "import nominatim database and dump it to a json like files in (useful for developing)")
     private String jsonDump = null;
 
diff --git a/src/main/java/de/komoot/photon/elasticsearch/IndexSettings.java b/src/main/java/de/komoot/photon/elasticsearch/IndexSettings.java
index 84f1a65f8..b077cc132 100644
--- a/src/main/java/de/komoot/photon/elasticsearch/IndexSettings.java
+++ b/src/main/java/de/komoot/photon/elasticsearch/IndexSettings.java
@@ -2,9 +2,13 @@
 
 import org.elasticsearch.client.Client;
 import org.elasticsearch.common.xcontent.XContentType;
+import org.json.JSONArray;
 import org.json.JSONObject;
 import org.json.JSONTokener;
 
+import java.io.BufferedReader;
+import java.io.FileReader;
+import java.io.IOException;
 import java.io.InputStream;
 
 /**
@@ -41,6 +45,45 @@ public IndexSettings setShards(Integer numShards) {
         return this;
     }
 
+    /**
+     * Add query-time synonyms to the search analyzer.
+     *
+     * Synonyms need to be supplied in a simple text file with one synonym entry per line.
+     * Synonyms need to be comma-separated. Only single-term synonyms are supported at this
+     * time. Spaces in the synonym list are considered a syntax error.
+     *
+     * @param synonymFile File containing the synonyms.
+     *
+     * @return This object for chaining.
+     */
+    public IndexSettings setSynonyms(String synonymFile) throws IOException {
+        if (synonymFile == null) {
+            return this;
+        }
+
+        insertJsonArrayAfter(settings, "/analysis/analyzer/search_ngram/filter", "lowercase", "extra_synonyms");
+        insertJsonArrayAfter(settings, "/analysis/analyzer/search_raw/filter", "lowercase", "extra_synonyms");
+
+        BufferedReader br = new BufferedReader(new FileReader(synonymFile));
+
+        JSONArray synonyms = new JSONArray();
+        String line;
+        while ((line = br.readLine()) != null) {
+            if (line.indexOf(' ') >= 0) {
+                throw new RuntimeException("Synonym list must not contain any spaces or multi word terms.");
+            }
+            synonyms.put(line.toLowerCase());
+        }
+
+        JSONObject filters = (JSONObject) settings.optQuery("/analysis/filter");
+        if (filters == null) {
+            throw new RuntimeException("Analyser update: cannot find filter definition");
+        }
+        filters.put("extra_synonyms", new JSONObject().put("type", "synonym").put("synonyms", synonyms));
+
+        return this;
+    }
+
     /**
      * Create a new index using the current index settings.
      *
@@ -65,4 +108,29 @@ public void updateIndex(Client client, String indexName) {
         client.admin().indices().prepareUpdateSettings(PhotonIndex.NAME).setSettings(settings.toString(), XContentType.JSON).execute().actionGet();
         client.admin().indices().prepareOpen(PhotonIndex.NAME).execute().actionGet();
     }
+
+    /**
+     * Insert the given value into the array after the string given by positionString.
+     * If the position string is not found, throws a runtime error.
+     *
+     * @param obj            JSON object to insert into.
+     * @param jsonPointer    Path description of the array to insert into.
+     * @param positionString Marker string after which to insert.
+     * @param value          Value to insert.
+     */
+    private void insertJsonArrayAfter(JSONObject obj, String jsonPointer, String positionString, String value) {
+        JSONArray array = (JSONArray) obj.optQuery(jsonPointer);
+        if (array == null) {
+            throw new RuntimeException("Analyser update: cannot find JSON array at" + jsonPointer);
+        }
+
+        for (int i = 0; i < array.length(); i++) {
+            if (positionString.equals(array.getString(i))) {
+                array.put(i + 1, value);
+                return;
+            }
+        }
+
+        throw new RuntimeException("Analyser update: cannot find position string " + positionString);
+    }
 }
diff --git a/src/main/java/de/komoot/photon/elasticsearch/Server.java b/src/main/java/de/komoot/photon/elasticsearch/Server.java
index 9cdf45474..0919cad17 100644
--- a/src/main/java/de/komoot/photon/elasticsearch/Server.java
+++ b/src/main/java/de/komoot/photon/elasticsearch/Server.java
@@ -178,14 +178,14 @@ public DatabaseProperties recreateIndex(String[] languages) throws IOException {
         return dbProperties;
     }
 
-    public void updateIndexSettings() {
+    public void updateIndexSettings(String synonymFile) throws IOException {
         // Load the settings from the database to make sure it is at the right
         // version. If the version is wrong, we should not be messing with the
         // index.
         DatabaseProperties dbProperties = new DatabaseProperties();
         dbProperties.loadFromDatabase(getClient());
 
-        loadIndexSettings().updateIndex(getClient(), PhotonIndex.NAME);
+        loadIndexSettings().setSynonyms(synonymFile).updateIndex(getClient(), PhotonIndex.NAME);
 
         // Sanity check: legacy databases don't save the languages, so there is no way to update
         //               the mappings consistently.