WordPress at a glance
filter is not described

mce_external_languages filter-hook . WP 2.5.0

Filters the translations loaded for external TinyMCE 3.x plugins.

The filter takes an associative array ('plugin_name' => 'path') where 'path' is the include path to the file.

The language file should follow the same format as wp_mce_translation(), and should define a variable ($strings) that holds all translated strings.

Usage

add_filter( 'mce_external_languages', 'filter_function_name_1309' );
function filter_function_name_1309( $translations ){
	// filter...

	return $translations;
}
$translations(array)
Translations for external TinyMCE plugins.

Where the hook is called

_WP_Editors::editor_settings()
mce_external_languages
wp-includes/class-wp-editor.php 451
$mce_external_languages = apply_filters( 'mce_external_languages', array() );

Where the hook is used (in WP core)

Does not used.