The coconut tree (Cocos nucifera) is a member of the palm tree family (Arecaceae) and the only living species of the genus Cocos. The term "coconut" (or the archaic "cocoanut") can refer to the whole coconut palm, the seed, or the fruit, which botanically is a drupe, not a nut. The name comes from the old Portuguese word coco, meaning "head" or "skull," after the three indentations on the coconut shell that resemble facial features. They are ubiquitous in coastal tropical regions and are a cultural icon of the tropics. Cocos nucifera is a large palm, growing up to 30 m (100 ft) tall, with pinnate leaves 4–6 m (13–20 ft) long and pinnae 60–90 cm (2–3 ft) long; old leaves break away cleanly, leaving the trunk smooth. It is one of the most useful trees globally and is often referred to as the "tree of life." 
 

Fruits II

In botany, a fruit is a seed-bearing structure in flowering plants formed from the ovary after flowering.

Fruits are how flowering plants disseminate their seeds. Edible fruits, in particular, have long propagated using the movements of humans and animals in a symbiotic relationship that is the means for seed dispersal for the one group and nutrition for the other; in fact, humans and many animals have become dependent on fruits as a source of food.   

Nuts

A nut is a fruit composed of a hard shell and a seed, which is generally edible.

There is an additional requirement in botany that the shell does not open to release the seed (indehiscent). In a general context, a wide variety of dried seeds are called nuts, but in a botanical context, only ones that include the indehiscent fruit are considered true nuts.