diff --git a/ext/bg/js/database.js b/ext/bg/js/database.js
index 0de0505d..7a893fc0 100644
--- a/ext/bg/js/database.js
+++ b/ext/bg/js/database.js
@@ -85,25 +85,26 @@ class Database {
         return results;
     }
 
-    async findTermsBySequence(sequence, dictionary) {
+    async findTermsBySequence(sequence, mainDictionary) {
         if (!this.db) {
             throw 'Database not initialized';
         }
 
         const results = [];
         await this.db.terms.where('sequence').equals(sequence).each(row => {
-            // if (dictionary === row.dictionary) {
-            results.push({
-                expression: row.expression,
-                reading: row.reading,
-                tags: dictFieldSplit(row.tags),
-                rules: dictFieldSplit(row.rules),
-                glossary: row.glossary,
-                score: row.score,
-                dictionary: row.dictionary,
-                id: row.id,
-                sequence: typeof row.sequence === 'undefined' ? -1 : row.sequence
-            });
+            if (row.dictionary === mainDictionary) {
+                results.push({
+                    expression: row.expression,
+                    reading: row.reading,
+                    tags: dictFieldSplit(row.tags),
+                    rules: dictFieldSplit(row.rules),
+                    glossary: row.glossary,
+                    score: row.score,
+                    dictionary: row.dictionary,
+                    id: row.id,
+                    sequence: typeof row.sequence === 'undefined' ? -1 : row.sequence
+                });
+            }
         });
 
         return results;
diff --git a/ext/bg/js/dictionary.js b/ext/bg/js/dictionary.js
index 2b289a23..c20df400 100644
--- a/ext/bg/js/dictionary.js
+++ b/ext/bg/js/dictionary.js
@@ -144,10 +144,10 @@ function dictTermsGroup(definitions, dictionaries) {
     return dictTermsSort(results);
 }
 
-function dictTermsMergeBySequence(definitions) {
+function dictTermsMergeBySequence(definitions, mainDictionary) {
     const definitionsBySequence = {'-1': []};
     for (const definition of definitions) {
-        if (definition.sequence > 0) {
+        if (mainDictionary === definition.dictionary && definition.sequence > 0) {
             if (!definitionsBySequence[definition.sequence]) {
                 definitionsBySequence[definition.sequence] = {
                     reasons: definition.reasons,
diff --git a/ext/bg/js/options.js b/ext/bg/js/options.js
index b49c32da..0aa6d7c6 100644
--- a/ext/bg/js/options.js
+++ b/ext/bg/js/options.js
@@ -154,6 +154,10 @@ function optionsSetDefaults(options) {
 
         dictionaries: {},
 
+        dictionary: {
+            main: ''
+        },
+
         anki: {
             enable: false,
             server: 'http://127.0.0.1:8765',
diff --git a/ext/bg/js/settings.js b/ext/bg/js/settings.js
index c5a28a45..4d248304 100644
--- a/ext/bg/js/settings.js
+++ b/ext/bg/js/settings.js
@@ -60,7 +60,11 @@ async function formRead() {
         const title = dictionary.data('title');
         const priority = parseInt(dictionary.find('.dict-priority').val(), 10);
         const enabled = dictionary.find('.dict-enabled').prop('checked');
-        optionsNew.dictionaries[title] = {priority, enabled};
+        const main = dictionary.find('.dict-main').prop('checked');
+        if (main) {
+            optionsNew.dictionary.main = title;
+        }
+        optionsNew.dictionaries[title] = {priority, enabled, main};
     });
 
     return {optionsNew, optionsOld};
@@ -237,6 +241,18 @@ function dictionaryGroupsSort() {
     dictGroups.append(dictGroupChildren);
 }
 
+function dictionarySetMain(e) {
+    const mainDictionary = $(e.target).closest('.dict-group');
+    const mainDictionaryTitle = mainDictionary.data('title');
+
+    $('.dict-group').each((index, element) => {
+        const dictionary = $(element);
+        if (dictionary.data('title') !== mainDictionaryTitle) {
+            dictionary.find('.dict-main').prop('checked', false);
+        }
+    });
+}
+
 async function dictionaryGroupsPopulate(options) {
     const dictGroups = $('#dict-groups').empty();
     const dictWarning = $('#dict-warning').hide();
@@ -247,13 +263,14 @@ async function dictionaryGroupsPopulate(options) {
     }
 
     for (const dictRow of dictRowsSort(dictRows, options)) {
-        const dictOptions = options.dictionaries[dictRow.title] || {enabled: false, priority: 0};
+        const dictOptions = options.dictionaries[dictRow.title] || {enabled: false, priority: 0, main: false};
         const dictHtml = await apiTemplateRender('dictionary.html', {
             title: dictRow.title,
             version: dictRow.version,
             revision: dictRow.revision,
             priority: dictOptions.priority,
-            enabled: dictOptions.enabled
+            enabled: dictOptions.enabled,
+            main: dictOptions.main
         });
 
         dictGroups.append($(dictHtml));
@@ -265,6 +282,11 @@ async function dictionaryGroupsPopulate(options) {
         dictionaryGroupsSort();
         onFormOptionsChanged(e);
     });
+
+    $('.dict-main').change(e => {
+        dictionarySetMain(e);
+        onFormOptionsChanged(e);
+    });
 }
 
 async function onDictionaryPurge(e) {
@@ -308,7 +330,7 @@ async function onDictionaryImport(e) {
 
         const options = await optionsLoad();
         const summary = await utilDatabaseImport(e.target.files[0], updateProgress);
-        options.dictionaries[summary.title] = {enabled: true, priority: 0};
+        options.dictionaries[summary.title] = {enabled: true, priority: 0, main: false};
         await optionsSave(options);
 
         await dictionaryGroupsPopulate(options);
diff --git a/ext/bg/js/templates.js b/ext/bg/js/templates.js
index c6de8580..4341322a 100644
--- a/ext/bg/js/templates.js
+++ b/ext/bg/js/templates.js
@@ -13,7 +13,9 @@ templates['dictionary.html'] = template({"1":function(container,depth0,helpers,p
     + alias4(((helper = (helper = helpers.revision || (depth0 != null ? depth0.revision : depth0)) != null ? helper : alias2),(typeof helper === alias3 ? helper.call(alias1,{"name":"revision","hash":{},"data":data}) : helper)))
     + "</small></h4>\n\n    <div class=\"checkbox\">\n        <label><input type=\"checkbox\" class=\"dict-enabled\" "
     + ((stack1 = helpers["if"].call(alias1,(depth0 != null ? depth0.enabled : depth0),{"name":"if","hash":{},"fn":container.program(1, data, 0),"inverse":container.noop,"data":data})) != null ? stack1 : "")
-    + "> Enable search</label>\n    </div>\n    <div class=\"form-group options-advanced\">\n        <label for=\"dict-"
+    + "> Enable search</label>\n        <label><input type=\"radio\" class=\"dict-main\" "
+    + ((stack1 = helpers["if"].call(alias1,(depth0 != null ? depth0.main : depth0),{"name":"if","hash":{},"fn":container.program(1, data, 0),"inverse":container.noop,"data":data})) != null ? stack1 : "")
+    + "> Set as main dictionary</label>\n    </div>\n    <div class=\"form-group options-advanced\">\n        <label for=\"dict-"
     + alias4(((helper = (helper = helpers.title || (depth0 != null ? depth0.title : depth0)) != null ? helper : alias2),(typeof helper === alias3 ? helper.call(alias1,{"name":"title","hash":{},"data":data}) : helper)))
     + "\">Result priority</label>\n        <input type=\"number\" value=\""
     + alias4(((helper = (helper = helpers.priority || (depth0 != null ? depth0.priority : depth0)) != null ? helper : alias2),(typeof helper === alias3 ? helper.call(alias1,{"name":"priority","hash":{},"data":data}) : helper)))
diff --git a/ext/bg/js/translator.js b/ext/bg/js/translator.js
index 81253374..3442124f 100644
--- a/ext/bg/js/translator.js
+++ b/ext/bg/js/translator.js
@@ -49,10 +49,11 @@ class Translator {
     }
 
     async findTermsMerged(text, dictionaries, alphanumeric) {
+        const options = await apiOptionsGet();
         const titles = Object.keys(dictionaries);
         const {length, definitions} = await this.findTerms(text, dictionaries, alphanumeric);
 
-        const definitionsBySequence = dictTermsMergeBySequence(definitions);
+        const definitionsBySequence = dictTermsMergeBySequence(definitions, options.dictionary.main);
 
         const definitionsMerged = dictTermsGroup(definitionsBySequence['-1'], dictionaries);
         for (const sequence in definitionsBySequence) {
@@ -62,7 +63,7 @@ class Translator {
 
             const result = definitionsBySequence[sequence];
 
-            const rawDefinitionsBySequence = await this.database.findTermsBySequence(Number(sequence));
+            const rawDefinitionsBySequence = await this.database.findTermsBySequence(Number(sequence), options.dictionary.main);
             const definitionsByGloss = dictTermsMergeByGloss(result, rawDefinitionsBySequence);
 
             // postprocess glossaries
diff --git a/tmpl/dictionary.html b/tmpl/dictionary.html
index f2f7f687..505331ea 100644
--- a/tmpl/dictionary.html
+++ b/tmpl/dictionary.html
@@ -3,6 +3,7 @@
 
     <div class="checkbox">
         <label><input type="checkbox" class="dict-enabled" {{#if enabled}}checked{{/if}}> Enable search</label>
+        <label><input type="radio" class="dict-main" {{#if main}}checked{{/if}}> Set as main dictionary</label>
     </div>
     <div class="form-group options-advanced">
         <label for="dict-{{title}}">Result priority</label>