an Arabic word instead of (Updated on) in meta line

hi there
I want to put an Arabic word (محدث) instead of (Updated on) in meta line.
So, where should I replace this word in PHP snippet or CSS ?
......
add_filter( 'generate_post_date_output', function( $output, $time_string ) {
$time_string = '<time class="entry-date published" datetime="%1$s" itemprop="datePublished">%2$s</time>';

$updated_time = get_the_modified_time( 'U' );
$published_time = get_the_time( 'U' ) + 3600;

if ( $updated_time > $published_time ) {
$time_string = '<time class="entry-date updated-date" datetime="%3$s" itemprop="dateModified">%4$s</time>';
}

$time_string = sprintf( $time_string,
esc_attr( get_the_date( 'c' ) ),
esc_html( get_the_date() ),
esc_attr( get_the_modified_date( 'c' ) ),
esc_html( get_the_modified_date() )
);

return sprintf( '<span class="posted-on">%s</span> ',
$time_string
);
}, 10, 2 );
...................
.updated-date:before {
content: "Updated on";
}
...............
Thanks in advance