Main Entry: ver·ti·cal

Pronunciation: \ˈvərt-i-kəl\

Function: adjective

: relating to or being transmission (as of a disease) by genetic inheritance or by a congenital or perinatal route <vertical transmission of the hepatitis B virus from mother to infant>—compare horizontal 2

—ver·ti·cal·ly \ˈvərt-i-k(ə-)lē\ adverb