hide text between <label>abc</label> - remove ' abc '
<label style="cursor: pointer; " for="31">
<img src="/joomla_1.7/images/stories/virtuemart/product/resized/black4_90x90.png" alt="the"/>
<span class="vm-img-desc" style="display: none; ">the</span>
$12.93
</label>

$('label').contents().last().remove();

$('#labelid').text('');
OR
$('.labelclass').text('');

empty()