fontanelle
noun /ˌfɒntəˈnel/
/ˌfɑːntəˈnel/
(US English usually fontanel)
(anatomy)- a space between the bones of a baby’s skull, which makes a soft area on the top of the baby’s headWord Originmid 16th cent. (denoting a hollow of the skin between muscles): from French, from modern Latin fontanella, from an Old French diminutive of fontaine, from late Latin fontana, feminine of Latin fontanus, adjective from fons, font- ‘a spring’. The current sense dates from the mid 18th cent.