In medical explaination, it means:
"A syndrome caused by a lesion of the seventh cranial nerve central to the geniculate ganglion and resulting in residual facial paralysis with profuse lacrimation during eating. Also called crocodile tears." - The American Heritage® Stedman's Medical Dictionary via The FreeDictionary.
or in common english, it means:
"..an uncommon consequence of recovery from Bell's palsy where faulty regeneration of the facial nerve causes sufferers to shed tears while eating. Keratoconjunctivitis sicca, more commonly known as dry eye, is a very common disorder of the tear film. Paradoxically, sufferers can experience watering of the eyes which is in fact a response to irritation caused by the original tear film deficiency."- via Wikipedia.