noun Whether you just brushed/combed your hair or not, it's the 1 - 3 strands of hair which stubbornly stick up, on the back of your head.
*Like the 'Little Rascals' character Alfalfa sported.
"Come here. You have an Alfalfa hair sticking up."
"No matter what I do, I still have these little Alfalfa hairs, on my head. I need to just snip them off."