Php variables in WordPress

To set a variable, such as an url, you can use the following steps:

• add to your wp-config a code with something like

require_once ABSPATH . 'wp-settings.php';
/** variabili */
define('GLOSSARIO_URL', 'yourwebsite/glossario.php');

• add to functions.php (in your wp theme root) something like

define('GLOSSARIO_URL', 'yourwebsite/glossario.php');

function glossario_link($atts) {
    $atts = shortcode_atts([
        'id' => '',
        'testo' => ''
    ], $atts);

    $url = GLOSSARIO_URL . '#' . $atts['id'];

    return '<a href="' . esc_url($url) . '">' . esc_html($atts['testo']) . '</a>';
}

add_shortcode('glossario', 'glossario_link');

• in wp editor you will be able to call that code inserting a text like this:

[glossario id="universalismo" testo="universalisticamente"]

where the content of testo="" is what will appears in your wp page (while in the editor you will see that code)