Replace text label

functions.php

<?php
add_filter( 'gettext_with_context', 'rt_mt_change_ticket_label', 99, 3 );
add_filter( 'gettext', 'rt_mt_change_ticket_label', 99, 3 );

function rt_mt_change_ticket_label( $translated_text, $untranslated_text, $domain ) {

    $replace_pairs = array(
        'Tickets'    => 'Entries',
        'Ticket'     => 'Entry',
        'Ticketed'   => 'Entered',
        'Unticketed' => 'Unentered',
        'New ticket' => 'New entry'
    );

    $translated_text = strtr( $translated_text, $replace_pairs );

    return $translated_text;
}