How can I get the taxonomy title from its machine name? (drupal 7)
The correct way to obtain a Label of a taxonomy vocabulary would be something like this:

$vocabulary = taxonomy_vocabulary_machine_name_load('machine_name');
echo check_plain($vocabulary-&gt;name);


However, looking at your screenshot, I guess you actually want to have the field Label of the taxonomy reference field. 

In that case your question is a duplicate of How do I get a field label by the field name?