nyctophobia

Are you afraid of the dark?

If the answer is yes, you might have nyctophobia, the abnormal fear of night or darkness. Derived from the Greek nux for "night" and phobia meaning "an aversion," nyctophobia is the perfect word for anyone who hides under the covers once the lights go out.

If you'd rather sleep in a coffin than a bed, you'll feel nice and cozy with our next word.