Come (6)
'come' is the definition.
(I know that come can be written as arrive)
This is all the clue.
(Other definitions for arrive that I've seen before include "Come to; succeed" , "Reach destination or achieve success" , "To gain recognition" , "Make it" , "Show up" .)
(Other definitions for together that I've seen before include "Collected" , "as a group" , "In one another's company" , "On the trot" , "in concert" .)