### Clue: Water right for fellow in one ship (8)
### Answer: IRRIGATE 
 ### Explanation: Definition: Water
 R(abbrev. for "right") **replacing**(for) "F"(abbrev. for "Fellow", see 26 across) **in** [ I(Roman numeral for "one") + "frigate"(a warship) ].
Defn: … as a verb.