Get across (6)
'get across' is the definition.
(thesaurus)
This is the entire clue.
(Other definitions for convey that I've seen before include "Make known -- pass on" , "Pass on or transport" , "Transport or transmit" , "Transport; communicate" , "Carry from one place to another" .)
(Other definitions for relay that I've seen before include "track event" , "supplementary store of anything" , "Hand, pass on" , "Receive and pass on - race" , "Team of workers" .)