Fresh water is provided by restaurant staff (7)
I believe the answer is:
waiters
'fresh water is provided by restaurant staff' is the definition.
I can't tell whether this defines the answer.
'fresh water is provided by' is the wordplay.
'fresh' indicates an anagram (a fresh re-ordering of the letters).
'provided by' says to put letters next to each other.
'water' put after 'is' is 'iswater'.
'iswater' with letters rearranged gives 'WAITERS'.
Can you help me to learn more?
(Other definitions for waiters that I've seen before include "Servers at tables" , "Wariest kind of attendants" , "Table servers" , "Garcons" .)