Thanks for ur reply. But I guess I want to know how researchers in the field of environmental science or analytical chemistry think about these two terms, not necessarily how they are described in dictionaries. After checking the dictionaries, art people still don't understand what is aggregation and what is agglomeration of nanoparticles, do they?
Scientists should set a good example by not appropriating common words and using them in contradictory or divergent senses, as this leads to miscommunication. If the meanings of aqueous and aquatic are so discrepant from common usage, then scientists should not use those words but coin new ones. Jargon does have a place.
Aqueous describes a fluid with liquid water as (usually the sole) solvent. Other solid materials may also have been dissolved therein. If it's just water, you'd just say water. It's a chemical descriptor.
Aquatic refers usually to things living in water and their habitat, as opposed to living on land (terrestrial). If you want to get more specific, there are adjectives galore for different varieties of aquatic environment. It's a biological or environmental descriptor.
So while a fish can swim in an aqueous solution, and a chemist can analyze an aquatic sample, these refer to deliberate specific situations, not the general usage.