Call, ring (5)
I believe the answer is:
phone
I believe this is a double definition.
'call' is the first definition.
(phone can mean to call by telephone)
'ring' is the second definition.
(I know that ring can be written as phone)
(Other definitions for phone that I've seen before include "Covert monitoring of electronic exchanges" , "Short piece of electronic equipment" , "Communications device" , "Communication device" , "It converts sounds into signals and back again" .)