How do I hide the field label for a HiddenInput widget in Django Admin?

I've got a bit of Django form code that looks like this:

class GalleryAdminForm(forms.ModelForm):
    auto_id=False
    order = forms.CharField(widget=forms.HiddenInput())

And that makes the form field go away, but it leaves the label "Order" in the Django admin page. If I use:

order = forms.CharField(widget=forms.HiddenInput(), label='')

I'm still left with the ":" between where the field and label used to be.

How do I hide the whole thing?!