Clubs and amusement parks use special black light paint that glows different colors. You can also buy fluorescent black light bubbles, invisible black light ink, fluorescent black light carpet and even fluorescent black light hair gel. Ordinary highlighters work well as black light pens..
The definition of a nutrient is something that provides nourishment, food or substances necessary for growth. Protein is an example of a nutrient.
n. 1. (Biology) any substance containing nutrients, such as carbohydrates, proteins, and fats, that can be ingested by a living organism and metabolized into energy and body tissue. 2. (Cookery) nourishment in more or less solid form as opposed to liquid form: food and drink.