Molluscs: awful until I included a hint of aioli (7)
I believe the answer is:
nautili
'molluscs' is the definition.
(nautilus is a kind of mollusc)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for nautili that I've seen before include "Cephalopod molluscs" , "creatures in the sea" , "marine life" .)