Naturalist definition, a person who studies or is an expert in natural history, especially a zoologist or botanist. See more.
Nighttime leg cramps are a sudden intense pain in the thigh or calf. A cramp is a tight muscle that won't relax. They can be caused by mineral deficiency.
By Mayo Clinic Staff. Night leg cramps, also called nocturnal leg cramps, are painful, involuntary contractions or spasms of muscles in your legs, usually occurring when you're in bed. Night leg cramps usually involve your calf muscles, although muscles in your feet or thighs might cramp as well.