Dread being caught in seaweed (3)
I believe the answer is:
awe
'dread' is the definition.
(I've seen this in another clue)
'caught in seaweed' is the wordplay.
'caught in' indicates a hidden word.
'AWE' is hidden within 'seaweed'.
'being' acts as a link.
(Other definitions for awe that I've seen before include "Great wonder" , "Great dread" , "Wondrous fear" , "Fear; reverence" , "Respect combined with fear or wonder" .)