Symbol of resistance from duck alongside Titanic (5)
I believe the answer is:
omega
'symbol of resistance' is the definition.
(I've seen this in another clue)
'duck alongside titanic' is the wordplay.
'duck' becomes 'o' (resembles zero - 'duck' in cricket).
'alongside' says to put letters next to each other.
'titanic' becomes 'mega' (both can mean huge).
'o'+'mega'='OMEGA'
'from' is the link.
(Other definitions for omega that I've seen before include ""The Alpha and the ___"" , "completes a series" , "Ultimate letter" , "Foreign character" , "16 letter" .)