--- /dev/null
+<?php
+
+namespace Drupal\search_api_synonym\Export;
+
+use Drupal\Core\Plugin\PluginFormInterface;
+use Drupal\Component\Plugin\ConfigurablePluginInterface;
+
+/**
+ * Provides an interface for search api synonym export plugins.
+ *
+ * @ingroup plugin_api
+ */
+interface ExportPluginInterface extends PluginFormInterface, ConfigurablePluginInterface {
+
+ /**
+ * Get synonyms in the export format.
+ **
+ * @param array $synonyms
+ * An array containing synonym objects.
+ *
+ * @return string
+ * The formatted synonyms as a string ready to be saved to an export file.
+ */
+ public function getFormattedSynonyms(array $synonyms);
+
+}