something that grows on your head and in random gross places like some dick hair.

that thing that everyone (usually) has.

It hard to take care of
Makes you mad in the winter

In guitar terminology, 'hair' is a type of distortion that you get on an amp. It's a minor distortion that is in addition to the clean sound.

long dangly stuff that grows on your body

(noun) courage, boldness, wildness, balls, especially in "show hair", to demonstrate these qualities. Probably from mid-20th cent. surfer lingo. Related to "hairy" meaning difficult or frightening.

A furry thing that gets into your face when you sleep and grows on some living creature. It can also grow in your nose. Hair will get tangled and ruin your life, but it’s a great addition to your life!