Declaring goal is missing, and hold (5)
I believe the answer is:
cling
'hold' is the definition.
(I've seen this before)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for cling that I've seen before include "Be emotionally over-dependent" , "Hold on as for dear life" , "fast" , "Keep hold" , "Hold on tightly, refuse to abandon" .)