Distinction between 水果 and 果? On a certain website, the translation for fruit is 水果, but later on it tells me that it is also 果.
What is the distinction?
果 is the abstraction of all kinds of "production of flower". It could be fruit, or nut. 

水果 means "juicy fruit" literally, but it could be any "production of flowers" which tastes delicious, e.g banana. But usually, people don't call nuts 水果, but 坚果 instead.