<Tr> <Th> FMA </Th> <Td> 59819 </Td> </Tr> <Tr> <Td_colspan="2"> Anatomical terminology (edit on Wikidata) </Td> </Tr> <P> The philtrum (Latin: philtrum, Greek: φίλτρον philtron, lit . "love charm"), or medial cleft, is a vertical indentation in the middle area of the upper lip, common to many mammals, extending in humans from the nasal septum to the tubercle of the upper lip . Together with a glandular rhinarium and slit - like nostrils, it is believed to constitute the primitive condition for at least therian mammals . Monotremes lack a philtrum, though this could be due to the specialised, beak - like jaws in living species . </P> <P> In most mammals, the philtrum is a narrow groove that may carry dissolved odorants from the rhinarium or nose pad to the vomeronasal organ via ducts inside the mouth . </P>

The vertical groove in the upper lip is the